Amber inclusions.
The frozen Eocene.

In the summer of 2009, a fist-sized piece of Baltic amber lay under a stereo microscope in a Göttingen laboratory. Embedded within it, legs splayed and an abdomen on which the fine rows of bristles were still visible, was a fungus gnat of the family Mycetophilidae. Between its antennae hung a tiny droplet, not an air bubble but a solidified portion of gut content, forced out at the moment of death some forty million years ago. In life the animal had just been digesting the remains of a fungal spore. What the microscopy showed that day was not a fossilised insect in the classical sense. It was a single instant. One moment of the Eocene, held in polymer and light.

Moments like these are the real scandal of Baltic amber. Other fossil deposits of the world (Solnhofen, Messel, the Chinese Liaoning shales) hand down skeletons, impressions, shadows of pigment. Baltic succinite hands down behaviour. It preserves not the dead animal but the second before. It is precisely this taphonomic peculiarity that has made the Eocene amber forest one of the richest windows palaeontology possesses onto mid-Tertiary life on land, richer in number of specimens, in resolution and in range than almost any other Lagerstätte of the Cenozoic (Weitschat & Wichard 2002; Sadowski et al. 2017).

The account that follows is an attempt to light up this window systematically. It is written for collectors who want more than market valuations, for students looking beyond the textbook footnote, and for readers who have so far met the Eocene only as a piece of geological vocabulary. We begin with the process of preservation that made all of it possible. For without a precise understanding of taphonomy, every inclusion remains a decorative curiosity rather than a data point.

Taphonomy: how a moment becomes a fossil.

Taphonomy is the study of what happens between the death of an organism and its discovery as a fossil: everything that alters, destroys or, in rare strokes of luck, preserves the original biological information. The term comes from the Russian palaeontologist Ivan Antonovich Yefremov (1940), who recognised that the gaps in the fossil record are not random but follow laws governing the chance of preservation. In Baltic amber we meet these laws in one of their most extreme expressions.

The process falls into four phases, which in the research literature have become established as adhesion, entombment, polymerisation and diagenesis (Henwood 1993; Martínez-Delclòs et al. 2004).

Adhesion.

The Eocene source tree (whose identity we will return to) secreted from wounds in its bark a thin, free-flowing resin, a mixture of terpenes, sesquiterpenes, diterpenoid acids and higher-molecular precursors. This resin was at first sticky as fresh honey. On the bark, on hanging droplets, along rivulets that ran down the trunk, insects, arachnids, pollen grains, bristle fragments and fungal hyphae became stuck fast. Some observers have compared the process to a modern glue trap, which holds true insofar as certain animal groups are massively over-represented: everything that flies, crawls or is driven by the wind. Ground-dwelling large animals are almost entirely absent.

Entombment.

Fresh resin flowed over the trapped animal, often in several layers. This multi-phase build-up can still be seen microscopically on many pieces as "flow lines". Importantly, the inclusion did not dry out during this phase but was enclosed by a practically oxygen-free organic matrix. Anaerobic, antimicrobial, dehydrating. It is precisely these three properties, the triad of exceptional preservation, that prevent the two chief enemies of organic matter: oxidative decay and microbial breakdown (Stankiewicz et al. 1998).

Polymerisation.

Inside the resin droplet, chemical cross-linking reactions set in. Double bonds of the terpene molecules reacted with one another, short-chain components evaporated or polymerised, and the material hardened into copal, a tough resinous intermediate stage that we still know today from recent tropical forests. The time required for this lies in the range of years to centuries.

Diagenesis.

The decisive step came only millions of years later. Embedded in sediments (predominantly in the "Blue Earth" of the Samland peninsula, a glauconitic clay layer of the upper Eocene), the transformation into true amber was completed under pressure, moderate warming and the exclusion of oxygen. Succinic acid (succinite) formed, the characteristic content of three to eight per cent that gave Baltic amber its scientific name (Beck 1965; Wagner-Wysiecka 2018). Only now was the polymer chemically stable enough to outlast erosion, marine floods and glacial transport.

What happened to the animal itself during these tens of millions of years is aptly described by Stankiewicz and colleagues (1998) as "chemical mummification": the original proteins, lipids and chitin structures are replaced step by step by the surrounding polymer, without the macroscopic form being lost. What you see under the microscope is therefore a hollow cast of polymer, in which the finest sculpture (antennal segments less than twenty micrometres in diameter, scale structures of butterfly wings, mouthparts at sub-micrometre resolution) is preserved as negative and positive at once. The material itself is gone. The information remains.

The material itself is gone. The information remains.

"Amber does not preserve the animal, but the outline of its life."after Wilhelm Wichard, palaeoentomologist

The source-tree question: Pinus succinifera or umbrella pine?

Which tree produced the resin our material came from? The question sounds academic, but it is decisive for reconstructing the Eocene forest, and to this day it has not been settled.

In the nineteenth century Heinrich Conwentz, director of the West Prussian Provincial Museum in Danzig, dissected hundreds of wood and bark fragments that he had found as inclusions in Baltic amber. His "Monograph of the Baltic Amber Trees", published in 1890, described a pine genus that he, following Schubert (1858) and Caspary, named Pinus succinifera: an extinct relative of today's pines, supposed to have supplied the resin that gave it its name in enormous quantities across the Eocene forests of the Baltic shield. This view held, with occasional modifications, for over a century.

In 2009 Alexander Wolfe and co-workers published a study that kicked up a great deal of dust. Using high-resolution infrared spectroscopy and solid-state NMR, they compared the chemical signature of Baltic amber with the resins of various conifer families living today. The result: not a pine (Pinaceae) but the family Sciadopityaceae (the umbrella pines) came closest to the spectrum. Today only a single species of this once widespread gymnosperm family survives, the Japanese umbrella pine Sciadopitys verticillata. Wolfe's conclusion: the true amber tree was a relative of the Sciadopityaceae, and Pinus succinifera a taxonomic fiction.

The debate ran, and still runs, on controversial lines. Several later studies (for instance Seyfullah et al. 2018) stressed that chemical spectroscopy cannot pin down the source unambiguously, because after millions of years of polymerisation the resins of different conifers grow chemically closer to one another. Sadowski and colleagues (2017) argue on palaeobotanical grounds (pollen finds, wood inclusions, cone remains within the amber) that several tree species probably contributed to amber formation in parallel: alongside Sciadopityaceae also Cupressaceae (the cypress family, for example the redwood kinship) and possibly early Pinaceae as well. The picture of the Eocene amber forest is therefore, in all likelihood, that of a mixed forest in which several resin producers stood side by side.

For inclusion research this means, in practical terms, that the monolithic "single amber tree" has receded into the background. Today we speak more cautiously of the Baltic amber forest as a habitat shaped over several million years and across a wide range by what were probably several tree species. Pinus succinifera is now regarded as a nomen dubium and as a paraphyletic collective name for several resin producers, one that lost its claim to a single source tree long ago.

The Eocene ecosystem: a lost world.

Between 34 and 48 million years ago, the region we now call the Baltic lay beneath a very different sky. That broad span covers the middle to late Eocene and takes in both the formation of the resin and its later deposition in the sediments of the Blue Earth; the main formation phase of the Baltic resin itself falls, on the current consensus, more narrowly within the late Ypresian and early Lutetian, around 44 to 49 million years (GTS 2020). Mean annual temperatures ran between 16 and 20 °C, with high humidity and a growing season free of hard frosts. The Eocene climate at these latitudes corresponded roughly to the humid subtropics of present-day southern China or the Florida hinterland (Mosbrugger et al. 2005). There were no glacial ice caps; the Earth was a greenhouse world.

The plant inclusions allow us to reconstruct the forest that stood here. Pollen analyses reveal a mosaic: dominant conifers (Sciadopityaceae, Cupressaceae, Pinaceae, Taxodiaceae) set among deciduous and evergreen broadleaf components: oaks of various sections, beech relatives, hickories, elms, laurels, magnolias, Liquidambar (sweetgums) and Hamamelidaceae. The understorey held ferns, clubmosses and liverworts; damp sites carried sedges (Cyperaceae) and early palm relatives. Ginkgo leaves appear here and there, the last representatives of a genus once distributed worldwide that today survives only in a single relict species.

The animal life, as far as the inclusions allow us to read it, was correspondingly rich. The ecological niches of a warm-temperate mixed forest (leaf litter, trunk surface, canopy, flower layer) were all occupied, often by groups we now know from tropical forests. Termites, the ancestors of stick insects, early bees, ichneumon wasps in a range no Central European forest still offers today, flower-visiting beetles, hunting spiders with complex webs. What the amber lacks (large vertebrates, water birds, fish-eating reptiles) is missing not from the forest but from the sample: the resin caught only what was small enough to stay stuck.

The geographical position of the amber forest is the subject of old debates. For a long time Fennoscandia was assumed to be the main area of distribution, on the grounds that glacial drift had transported the amber southwards. More recent stratigraphic and redepositional work (Standke 2008) argues primarily for the identity of Baltic and Bitterfeld amber and for a source region in the Fennoscandian-Baltic transition zone, with the Blue Earth of Samland as the main marine depositional area; the more narrowly south-eastern siting in north-west Russia and Belarus derives rather from Polish work (Kasiński, Kramarska) and remains unresolved. The amber forests themselves, then, did not grow in the Baltic. The amber was washed there, deposited, and secondarily redistributed during Pleistocene glacial movements.

A systematic survey of the inclusions.

Several large-scale counts document the frequency distribution of inclusions in Baltic amber. Larsson (1978) examined more than 25,000 pieces for his standard study; Weitschat & Wichard (2002) revised and supplemented these figures using the Hamburg collection; Sontag (2003) provided comparative data on the Polish material. The numbers vary in detail, but the overall picture is robust: arthropods dominate absolutely, dipterans dominate within the arthropods, and anything large is rare.

Diptera: the dominant group.

More than half of all animal inclusions are true flies, and for three reasons: they were abundant in the Eocene forest, their way of life (flying just above the ground, the trunk and the canopy) brought them into constant contact with resin droplets, and their small body size gave them little power to free themselves again from the sticky secretion. Within the Diptera the dominant families are dark-winged fungus gnats (Sciaridae), fungus gnats (Mycetophilidae), gall midges (Cecidomyiidae) and moth flies (Psychodidae). Mosquitoes (Culicidae), the stars of popular amber mythology, are present, but considerably rarer than their non-biting relatives. The impression that every piece of amber contains "the Jurassic Park mosquito" is a distortion of mass culture.

Hymenoptera: ants and the early flowering of social insects.

Within the Hymenoptera, ants are by far the most common group. The Baltic amber ants, treated monographically above all by Wheeler (1915), Dlussky (1997, 2002) and more recent work by the Senckenberg group, are an evolutionary-biology treasure of the first rank. They show that the main lineages of modern ant systematics (Formicinae, Dolichoderinae, Myrmicinae) were already established in the Eocene. Inclusions with several animals of one species and morphological traces of caste differentiation document the social structure. Bees are rarer, but present; Electrapis (Cockerell 1908, revised Engel 2001), documented in Baltic amber, is discussed as a possible early record of social bee forms, although its actual degree of sociality is not conclusively established morphologically.

Coleoptera: the phylogenetic truffles.

Beetles make up little in terms of share, but they are scientifically over-represented in the literature because they often present transitional forms or relict groups that play key roles in the evolutionary history of the largest animal order on Earth. Weevils, rove beetles, deathwatch beetles, bark beetles, mould beetles: many families are documented in Baltic amber for the first time or in their best-preserved state (Hieke & Pietrzeniuk 1984).

Hemiptera, Arachnida, Lepidoptera.

Bugs and cicadas are widespread, often with well-preserved mouthparts that allow inferences about their host plants. Spiders, treated above all by Wunderlich (2004, 2008) in several large-volume monographs, cover roughly a dozen families in the Baltic material, a range that exceeds any present-day northern European spider fauna; pseudoscorpions sometimes offer the rare observation of phoresy, the practice of small arachnids hitching a ride on larger insects (Henderickx 2005). Butterflies and moths are the great frustration of amber lepidopterists: their soft, scale-covered wings almost always disintegrate on contact with the resin, so that usually only scales or isolated wing fragments remain. Complete Microlepidoptera specimens are extremely rare and correspondingly sought after by science.

Plant and microbial inclusions.

Pollen, spores, leaf fragments, flower dust, small flowers and wood splinters make up a substantial share of the inclusions and are the most important source for reconstructing the amber forest. Fungal hyphae occur regularly, some on or within animal inclusions, which suggests that some inclusions were already affected by an infection before they were enclosed. Bacteria and single-celled algae are detectable, but practically only visible at the highest magnification (Schmidt & Dilcher 2007).

Non-biological inclusions.

Not every enclosure is an inclusion in the narrower sense. Gas bubbles, liquid bubbles (often Eocene rain or plant exudates), pyrite discolouration, soil and plant material, even the occasional small stone particle: they all belong to the taphonomic reality of the material and are in truth often useful for assessing authenticity, because modern synthetic-resin imitations reproduce them only inadequately.

Vertebrate inclusions: the sensation class.

Here things become rare and difficult at the same time. Complete vertebrates practically do not occur in Baltic amber; the secretion was not durable enough for a reptile or a bird. What does exist are remains: feather fragments, individual skin scales of small lizards, occasionally mammalian hairs. The famous "Baltic lizard find", long cited as the gold standard, has been revised several times and partly discussed as secondary embedding or later manipulation; with critical care, only a few lizard inclusions in the Baltic material are today classified as beyond doubt. A comparably small number of feather fragments (for instance Sadowski et al. 2017) are regarded as securely of Tertiary origin. The spectacular vertebrate finds of recent decades come almost exclusively from the considerably older Burmese amber of the Middle Cretaceous, not from the Baltic material.

Lay all of these individual finds side by side on a table and you no longer see animals and pollen. You see an archive.

Inclusions as an archive of evolution.

The scientific value of Baltic amber inclusions lies not in the beauty of the individual pieces but in what they collectively reveal about the development of life. Four examples should suffice to suggest the range.

First, the history of the social insects. The oldest evidence for colony-forming ants comes from older Cretaceous material, but the Baltic Eocene yields by far the richest finds with recognisable caste structures: queens, workers, reproductives, and on occasion trophallaxis (the passing of food) at the very moment of entrapment. Here behaviour is not inferred but observed.

Second, the co-evolution of plants and pollinators. Inclusions of flower-visiting insects with pollen still adhering allow us to work out which insects visited which plants. Studies of hoverflies, early bees and flower-visiting beetles show that the pollination relationships familiar today were already established in the Eocene, partly through extinct and partly through unexpectedly modern partnerships.

Third, the evolution of spider web-building. A few inclusions contain spiders with fragments of web, the finest silk structures, which taphonomically one would hardly expect to survive, yet whose polymer replacement has preserved the exact arrangement of the sticky and supporting threads. From this it can be reconstructed that several modern principles of web construction (orb webs, funnel webs) already existed in the Eocene.

Fourth, the question of "living fossils". Some inclusion taxa are extinct today or confined to tiny relict ranges; others differ so little from their living relatives that an Eocene inclusion and a present-day animal can be laid side by side without the difference being apparent at first glance. This evolutionary standstill in certain groups, for example among fungus gnats or pseudoscorpions, is itself a biological statement.

Ten faces of a fossilised moment.

The first time you see an inclusion under a loupe, you get a small shock of reality. This is not the schematic butterfly-in-amber graphic from the school textbook. These are real animal remains, often half twisted, frequently fragmented, sometimes veiled by gas bubbles, and almost always smaller than you hope. By the counts of Weitschat and Wichard (2002), the following ten types cover roughly 95 per cent of what turns up in the collector trade, from the ubiquitous non-biting midge to the lizard that nearly always ends up in a museum. We go through them in order, with measurements, frequencies and identifying features.

The midge majority: Diptera as the background noise of every collection.

If you lay ten inclusion pieces from the collector trade side by side at random, five to seven of them will hold true flies. Depending on the count, Diptera make up 55 to 70 per cent of all animal inclusions in Baltic amber (Weitschat and Wichard 2002, p. 16; Grimaldi and Engel 2005, ch. 12). By far the most common are small midges of the family Chironomidae, the non-biting midges, along with Sciaridae (dark-winged fungus gnats) and Cecidomyiidae (gall midges). Larger biting mosquitoes of the family Culicidae are comparatively rare in the Eocene material and correspondingly more expensive.

Under the loupe you see a slender, segmented body, long thin legs, often longer than the body itself, two wings with clear venation, and in the males feathered or at least densely hairy antennae. If you can make out a long, needle-like proboscis, you are holding a culicid, a true biting mosquito. The famous mosquito from the opening image of Jurassic Park is often described as Anopheles, which would be wrong in two palaeontological respects, but we come to that in section 9.

The second large subgroup, the flies (Brachycera), looks stockier, has short antennae and usually broader wings. Common in the Baltic material are dance flies (Empididae), scuttle flies (Phoridae) and fungus gnats (Mycetophilidae, in the narrow sense counted among the Nematocera). A well-preserved fly with clearly visible eye facets and both wings usually sits above an average non-biting midge in the collector price, because its anatomy is less delicate and therefore stays more visible.

A category in its own right for enthusiasts is mating inclusions: two flies or midges still attached to one another, frozen in the act. Such pieces reliably command a premium of 50 to 200 per cent over a single inclusion, because the image of a stopped moment always finds a collector willing to pay for it. Penney (2010, ch. 4) documents several such copulation inclusions from the Baltic Eocene. The midges are therefore not only the background noise but also the entry point to understanding what the market pays extra for.

Spiders and beetles: the armoured middle tier of the collection.

Spiders (Araneae) make up around 10 per cent of the Baltic arthropod inclusions; together with the related mites and pseudoscorpions, the arachnids (Arachnida) reach up to 15 per cent (Wunderlich 2004, Beiträge zur Araneologie, vol. 3). They are easy to identify by the eight-legged build, the clearly divided body of cephalothorax and opisthosoma, and the often visible chelicerae region at the front of the head. Common are orb-weavers (Araneidae), jumping spiders (Salticidae) and tube-dwelling spiders (Segestriidae). A visible spider in a clear, well-polished piece typically sits at 50 to 300 euros each on the German collector market, and considerably higher for top material with a prey scene.

It becomes palaeontologically exciting when, alongside the spider, remains of silk threads become visible, fossil web fragments in which other, smaller insects have become trapped. Such prey-with-predator pieces are sought after, and Penney (2010) describes them as the most important source of directly documented predator-prey behaviour in the Eocene. The Natural History Museum in Vienna holds a piece with a spider plus several prey insects in the web, whose insured value is given in the order of several tens of thousands of euros. The scene here is worth more than the single animal.

Beetles (Coleoptera) make up 3 to 5 per cent of the animal inclusions in the Baltic material (Hieke and Pietrzeniuk 1984; Alekseev 2013), but for many collectors they are the aesthetically most appealing pieces of all. Common are weevils (Curculionidae), rove beetles (Staphylinidae) and small lamellicorn beetles of the superfamily Scarabaeoidea. The identifying feature is the hard, often glossy chitinous shell with the forewings transformed into elytra, and the body clearly divided into three parts with a visible head, pronotum and abdomen.

A complete beetle of four to six millimetres body length with both elytra, all six legs and an intact head, clearly visible in clear amber, is a collector's object. Market prices on the German collector market typically sit at 30 to 150 euros each, reaching several times that for larger longhorn beetles (Cerambycidae) or well-preserved jewel beetles (Buprestidae). Spiders and beetles together form what you might call, in practice, the armoured middle tier of a serious collection: common enough to be findable, rare enough still to earn admiration when the cabinet is opened.

Ants, bees, wasps: the colony-building Hymenoptera.

Depending on the count, Hymenoptera make up 5 to 15 per cent of the Baltic animal inclusions (Weitschat and Wichard 2002; Sontag 2003), and within this group ants (Formicidae) are by far the most common representatives, at around 70 to 80 per cent. They are easy to recognise by the characteristically segmented body with the narrow waist between mesosoma and gaster, the petiole, and by the elbowed antennae typical of the family. The Baltic material is dominated by workers from the subfamilies Formicinae and Dolichoderinae, which still exist today but are represented by numerous extinct genera, along with the now relictual Aneuretinae; occasionally winged reproductives from nuptial flights are also found (Dlussky 1997).

A category of its own is the so-called social inclusions: several ants in the same piece, sometimes more than ten animals at once, which evidently entered a larger resin pool in a mass fall. Such pieces are especially valuable palaeontologically, because they document behaviour, not just anatomy, and so give information about colony size and activity patterns (LaPolla et al. 2013, Annual Review of Entomology). On the German collector market, social inclusions with at least three clearly visible animals typically fetch 100 to 500 euros each, and more for special behavioural scenes.

Bees and wasps (Apocrita) are rarer than ants but more unmistakable. The distinctly narrowed wasp waist between thorax and abdomen, the often dense hairiness in bees, the clearly visible membranous wings with characteristic venation, all of this makes assignment to the superfamily easy. In Baltic amber, especially small solitary bees and ichneumon wasps of the superfamily Ichneumonoidea are common.

A note for buyers: true honeybees of the genus Apis are not documented in the Baltic Eocene; the oldest confirmed Apis fossils come from the Oligocene (Engel 2001). What collectors are often offered as a bee in amber is usually a small solitary bee of the family Melittidae or an ichneumon wasp. Anyone buying out of love for the honeybee as an animal should know this and not be led by the description in the auction text. The solitary bee is still a fine and scientifically valuable piece.

Plants, water, air: what else, besides animals, sits in the resin.

Plant inclusions are chronically underrated. Depending on the estimate, they make up 5 to 15 per cent of all inclusions and are often the scientifically most informative pieces of all, because they help reconstruct the forest from which the resin flowed (Sadowski et al. 2017, Earth-Science Reviews). Especially common in the Baltic material: pine and cedar needles in bundles of two or three, leaf fragments of oaks (Fagaceae) and laurels (Lauraceae), pollen grains, microscopically small but clearly visible under polarised light, along with moss cushions and individual flowers.

A complete, three-dimensional flower in amber, for instance of the Eocene Symplocaceae genus Eotrigonobalanus or of a laurel, is a rarity of the first order and sits in the five-figure range (Sadowski, Schmidt and Seyfullah 2018, Fossil Imprint). Plant inclusions are often cheap for collectors to acquire, because the broad market scarcely demands them; for palaeobotanists, by contrast, they are treasures. Anyone who buys against the cycle here builds a scientifically relevant collection at prices below those of comparably well-preserved insects.

Water droplets and gas bubbles are, strictly speaking, not inclusions in the palaeontological sense but physical enclosures. Water droplets, often visible as small lenses, sometimes with a mobile air bubble inside that collectors jokingly call a water-level gauge, are aesthetically pretty but valued low economically, usually 20 to 100 euros each on the German collector market. Anyone who finds a piece with a mobile bubble has a curiosity, not an investment piece.

Important for authenticity testing: gas bubbles directly around an animal inclusion are a reliable mark of authenticity. They form when the animal drags air in as it falls into the resin, or when decomposition releases small amounts of putrefaction gas. Such accompanying structures are hard to reproduce in modern fakes, because they cannot be inlaid but can only arise in genuine resin flow (Grimaldi 1996, Amber: Window to the Past). More on this in the authenticity section.

Feathers and vertebrates: the extreme rarities.

Feathers are extremely rare in Baltic amber. When they do appear, it is usually as small fragments or single down feathers, occasionally as complete contour feathers of small songbirds. So far, fewer than a hundred feather inclusions from the Baltic material have been scientifically published (compare Perrichot et al. 2008, Acta Palaeontologica Polonica, on the methodology of feather identification in fossil resin). In Burmese amber, by contrast, feathers are more common and in part exceptionally preserved, including the feathered tail fragment of a non-avian coelurosaur published in 2016 by Xing et al. (Current Biology). Market prices for clearly identifiable feather inclusions in Baltic amber sit at 1,000 to 3,000 euros each.

Mammal hairs are similarly rare, but occasionally documented (Weitschat and Wichard 2002, pp. 240ff). A clearly identifiable tuft of hair in Baltic amber typically sits at 800 to 2,500 euros each on the collector market. Anyone owning such a piece should be aware of its scientific relevance: every new hair extends knowledge of the Eocene mammal fauna, which otherwise has left scarcely any direct traces in amber.

The rarest and most expensive category is vertebrate inclusions. In the Baltic material they are so rare that every single piece is documented worldwide and as a rule ends up in a museum. The known examples can be counted on one hand: a lizard foot in the Geological-Palaeontological Institute in Hamburg, several lizard fragments in Palanga, a frog of the genus Eleutherodactylus in the Natural History Museum in Vienna (this one in Dominican, not Baltic material). According to estimates by various authors, the frequency is less than one in ten thousand, possibly closer to one in a hundred thousand (Borkent 1995; Penney 2010).

Market prices are hardly meaningful to give, because such pieces do not pass through the normal trade. When they do, it is in the five-figure range for fragments and the six-figure range for complete specimens. A complete lizard or a frog in Baltic amber belongs in a museum, not in a private cabinet. Anyone who believes they own one should not sell the piece on their own initiative, but first have it examined by a specialist museum. Both the institute in Hamburg and Palanga and the Museum für Naturkunde in Berlin carry out free preliminary examinations.

A practical note on scale, which applies to all ten types: most collector inclusions are small, often 2 to 5 millimetres in body length. Anyone who owns a piece and believes they see a large inclusion should measure it first. A midge of 8 millimetres would already be exceptionally large for Baltic amber. What looks like a large insect is often a small plant structure, a flow artefact or, less happily, a modern insect in an imitation.

DNA in amber: the Jurassic Park complex.

Few scientific subjects have shaped the popular image of amber as thoroughly as the 1993 Hollywood film. The idea of recovering dinosaur blood from the stomach contents of a trapped mosquito and reconstructing a living tyrannosaur from it by DNA analysis is brilliant as storytelling. It is also scientifically wrong, and the route by which that conclusion was reached is itself an instructive story about the self-correcting capacity of research.

In September 1992 and June 1993, almost in step with the film, two attention-grabbing studies appeared. DeSalle and co-workers reported in Science on the extraction and sequencing of insect DNA from a termite in 25–30 million-year-old Dominican amber. Cano and colleagues claimed something similar in 1993 in Nature 363 for a weevil from Lebanese amber (over 120 million years old). Both papers were read worldwide. The scientific amber world was electrified.

It did not stay that way for long. As early as the mid-1990s, Höss and co-workers, along with Austin and colleagues, reported the first unsuccessful replication attempts. The DNA fragments sequenced as "Eocene" or "Cretaceous" could not be reproduced, and their sequence homologies showed suspiciously modern characteristics. The methodologically decisive study appeared two decades later: Penney, Wadsworth, Fox and co-workers (2013), and in parallel Smith & Austin (2014), carried out replication attempts on copal inclusions using modern next-generation sequencing methods and the strictest contamination protocols, that is, on material only a few thousand to at most a few tens of thousands of years old. No endogenous insect DNA was found there either. If even young copal contains no preserved DNA, then amber millions of years old certainly does not.

The explanation comes from DNA chemistry itself. Allentoft and co-workers (2012) calculated the half-life of DNA from a large sample of dated bone finds, that is, the time span over which one in every two nucleotide bonds is statistically broken. Under the most favourable conditions it is about 521 years. Even extrapolated to optimally cool and dry storage conditions, after around 1.5 million years no readable fragment remains statistically. Forty million years therefore lie far beyond the expected limits of preservation according to the current understanding of DNA diagenesis. What Cano had sequenced at the time was in all probability modern laboratory contamination, a plausible explanation that, incidentally, does not personally discredit him; the methods of the day simply could not reliably rule out contamination.

What remains in amber, then, is not DNA but structure. The finest anatomical information (sensory bristles, mouthparts, genital structures, and in rare cases even internal organs) can be preserved under favourable conditions. Occasionally, chemical traces of original biomolecules can be detected (pyrolysis GC-MS has identified chitin breakdown products, for example), but sequenceable genetic material is not among them. Anyone who wants to clone a dinosaur will have to find a different material. A living bird in the garden is closer to a velociraptor than any amber inclusion.

What the DNA did not outlast, the polymer did: the finest wing venation, sensory bristles, every curve of the antennae, trapped water droplets included, frozen in place around 40 million years ago.

The methodological toolkit of modern inclusion research.

Classical amber-inclusion research of the nineteenth and early twentieth centuries worked with a hand lens, a stereomicroscope and a steady hand. These tools are by no means obsolete. Careful stereomicroscopy at forty to one hundred times magnification still does the bulk of the identification work today. But over the past two decades the methodological toolkit has gained an extension that has lifted the study of inclusions into a new phase.

The greatest revolution came with synchrotron micro-computed tomography. An intense, coherent X-ray beam penetrates the piece of amber and delivers three-dimensional section images of the inclusion at micrometre resolution, without having to grind, saw or otherwise damage the piece. Sadowski and colleagues (2017) used this method to reconstruct Eocene spider taxa, for instance, whose ventral side was invisible under conventional microscopy because the animal lay embedded face down. Today inclusions can be virtually "opened up", rotated and stripped away layer by layer, without losing so much as a single molecule of the original substance. For the description of new species this is close to a paradigm shift.

The great collections.

Anyone who wants to study Baltic amber scientifically cannot avoid a small number of central collections. Some are open to the public, others only to researchers, but together they form the backbone of the discipline.

Geoscience Centre of the University of Göttingen (GZG).

Home to the historic Königsberg amber collection, which reached Göttingen by roundabout routes after the Second World War. Originally built up from the late nineteenth century at the Geological-Palaeontological Institute of the Albertina in Königsberg under Richard Klebs, and expanded between the wars partly through the work of Bachofen-Echt (whose work emerged in an East Prussian and Austrian scientific milieu of the 1920s and 1930s that collectors today should read with the necessary historical distance), it is now one of the most valuable holdings in the world, with numerous holotypes, that is, the original described specimens of new species. Anyone who wants to verify historical first publications comes to Göttingen.

Senckenberg Research Institute Frankfurt.

A significant part of modern amber hymenopterology is carried out here. The collection comprises both Baltic and international material and is the first port of call in particular for identification comparisons of ant inclusions.

Geological-Palaeontological Museum Hamburg.

Home of the Weitschat-Wichard collection, the basis of the standard reference work "Atlas der Pflanzen und Tiere im Baltischen Bernstein" (2002). One of the best documented and most intensively studied collections in the world.

Museum für Naturkunde Berlin.

Holds, among other things, parts of the Klebs collection and the Schaufus collection. Klebs's systematic study of Baltic inclusions at the end of the nineteenth century is one of the pioneering methodological achievements, embedded in the East Prussian and colonial scientific establishment of Königsberg at the time, whose holdings passed through several intermediate stages into present-day German collections after 1945.

Amber Museum Ribnitz-Damgarten.

The only museum in Germany devoted solely to amber. More ethnographic and cultural-historical than purely scientific in orientation, but with a large, representative inclusion display for the public.

Amber Museum Palanga (Lithuania).

Housed in the Tiškevičius Palace on the Lithuanian Baltic coast. Home to one of the largest public amber exhibitions in Europe, with a particular focus on Baltic material from its immediate source region.

Manchester Museum (United Kingdom).

Base of the research group around David Penney, one of the leading modern amber researchers. Its focus is on arachnid inclusions and on the DNA replication studies already mentioned.

Three forests, three worlds: where inclusion amber really comes from.

Pick up a piece with an inclusion and you rarely hold just an animal in resin. You hold a forest. Three of these forests have made it into today's collector market, and they are so different that you really ought to display them in three separate cabinets. The Eocene coastal forest of Samland 44 to 49 million years ago, where our Baltic succinite flowed. The Miocene rainforest of Hispaniola 16 to 20 million years ago, the source of Hymenaea protera resin. And the Cretaceous Hukawng forest in northern Myanmar, around 99 million years ago, when small, non-avian coelurosaurs still ran through the undergrowth. Three provenances, three faunas, three very different ethical situations.

Baltic: the standard everything is measured against.

Let us begin with the material that sits in almost every German collector's cabinet. Baltic amber, mineralogically succinite, formed in the middle Eocene, 44 to 49 million years ago, in a subtropical forest belt whose sediments now surface on the Samland peninsula (Kaliningrad). The main deposits lie in Kaliningrad (the Blue Earth of the Prussian Formation), Poland and Lithuania. Bitterfeld amber from Saxony-Anhalt is, according to Standke (2008), very probably identical to Baltic material that was redeposited into central German sediments in the Oligocene. Chemically, succinite is unmistakable: 3 to 8 per cent succinic acid (succinite, hence the name), and an FTIR spectrum with the characteristic so-called Baltic shoulder in the 1250 to 1175 cm⁻¹ range, which no other fossil resin in the world shows in this form (Beck 1965; Weitschat and Wichard 2002). Anyone with a laboratory to hand can separate Baltic amber from all other provenances within minutes.

The source-tree question remains open, and that is a small scientific punchline in its own right. Heinrich Conwentz proposed in 1890 the thesis of a single mother species, Pinus succinifera, and Heinrich Schubert supplied wood-anatomical arguments in the same direction in 1961, without settling the question conclusively. Generations of textbooks adopted it. Since the 2000s, however, the spectroscopic findings that do not fit have been piling up. Above all, succinite lacks the abietic acid that marks every modern pine resin. Wolfe and colleagues proposed Sciadopityaceae in 2009 in the Proceedings of the Royal Society B, a family represented today only by the Japanese umbrella pine Sciadopitys verticillata. Sadowski et al. (2017) confirmed the direction with cuticular remains. Baltic amber may be a mixed product of several trees, or it may come from an extinct conifer with no modern relatives. The only certainty is that the old textbook story is wobbling.

For the collector market, a different number counts. More than 3,500 species have been described from Baltic amber, more than from any other amber in the world (Weitschat and Wichard 2002; Penney 2010). The proportions are well mapped: true flies (Diptera) dominate at 55 to 70 per cent, Hymenoptera (above all ants) lie at 5 to 15 per cent, spiders and mites together at 10 to 15 per cent, beetles at 3 to 5 per cent. Vertebrates are so rare that every piece is listed worldwide. This is exactly why Baltic amber is the reference: anyone wishing to compare a midge from Palanga with one from the Dominican Republic is comparing a well-documented standard material with a special provenance. In the German market, Baltic pieces make up an estimated 85 to 90 per cent of all appraised inclusions. What you, as a collector in northern Germany, end up holding is in all likelihood Samland material from the Eocene. That also defines the range in which bernsteinmobil operates: Baltic succinite, the only type of amber we routinely appraise.

Dominican: younger, clearer, more dramatic.

Let us jump forward around 25 million years and half a globe further, to Hispaniola. Dominican amber comes from the Miocene, so 16 to 20 million years old (Iturralde-Vinent and MacPhee 1996, dated via foraminifera of the enclosing mudstones), mined in the La Toca and the Yanigua formations in the Cordillera Septentrional north of Santiago. Source tree: Hymenaea protera (Poinar 1991), an extinct relative of today's tropical carob trees. The material is immediately distinguishable from the Baltic by eye. It is clearer, more glass-like, often honey-yellow to deep red. A small subgroup, the famous blue amber from the mines around La Cumbre and Palo Quemado, shows an intense blue fluorescence under UV light; in high-grade top material from La Cumbre this also flashes through at certain angles in diffuse daylight, whereas ordinary blue Dominican amber needs the UV lamp. This variety is regarded on the international market as top quality and fetches raw prices of 30 to 80 euros per gram (as of 2024 to 2026, wholesale), without a single midge sitting in it.

The faunal assemblage is younger and therefore, for the layperson, closer to what they would see on a Caribbean walk. Termites of the genus Mastotermes, ants, small orb-weaver spiders, solitary bees, but above all the thing that really carries the Dominican market: reptiles. Anolis lizards, occasionally frogs of the genus Eleutherodactylus, sometimes scorpions. The famous frog in the Natural History Museum in Vienna, an animal roughly 15 to 20 millimetres long in a honey-yellow lump, is a Dominican piece and probably the most photographed amber inclusion in the world. A comparable piece in Baltic material simply does not exist. Anyone who collects reptiles almost inevitably collects Dominican.

Among German collectors, Dominican amber is the exotic alternative. The pieces often look more impressive, but they have a different market character. Per gram of raw material the prices sit at a similar level to Baltic amber (raw 5 to 30 euros per gram with good clarity), yet the individual inclusion piece often fetches higher peak values, because the inclusions themselves look more dramatic. A complete Anolis lizard in a clear Dominican piece, cleanly cut and polished, lies in the high four-figure to low five-figure range. For appraisal through bernsteinmobil a clear note applies: we concentrate exclusively on Baltic material. Anyone with a Dominican piece they want worked on is better served by specialist auction houses (Heritage Auctions, Aguttes), which have traded the Caribbean material for decades.

Burmese: 99 million years, and a political problem.

Now it becomes palaeontologically exciting and ethically uncomfortable. Burmese amber, traded as Burmite, comes from the Hukawng Valley in Kachin State in northern Myanmar. Its age lies in the lowermost Cenomanian of the Cretaceous, precisely dated at 98.8 plus or minus 0.6 million years by U-Pb dating of zircons from the enclosing volcaniclastic sediments (Shi et al. 2012, Cretaceous Research). That makes Burmite twice as old as Baltic amber and around five times as old as Dominican. The source trees are thought to be Araucariaceae relatives, possibly several conifer lineages at once (Poinar et al. 2007). The material is mostly deep red-brown to cherry-red, often with clear flow streaks, and yields the palaeontologically most important inclusions in the world.

The finds are what collectors have dreamed of since Jurassic Park. In December 2016, Lida Xing published in Current Biology a tail fragment of a small, non-avian coelurosaur, complete with feathers. June 2016 and June 2017 brought, in Nature Communications, two bird nestlings of the Enantiornithes, Cretaceous birds with teeth and claws on the wing. One of the finds, a hatchling with skull and complete wings, shows almost the entire animal with skin, plumage and legs. Frogs (Electrorana limoae, described by Xing et al. 2018 in Scientific Reports), lizards, snakes, even a basal member of the snake lineage (Xiaophis myanmarensis) are documented in Burmite. What does not appear in 3,500 scientific papers on Baltic amber turns up in abundance in Burmite. The reason is age plus faunal density plus apparently especially favourable preservation conditions in the Cretaceous Hukawng forest.

And this is exactly where the problem begins. The Hukawng deposits lie in the middle of the conflict zone between the Myanmar military government and the Kachin Independence Army. According to investigations by the New York Times (2019) and a statement by the Society of Vertebrate Paleontology (the president's letter to members, April 2020), proceeds from the amber trade finance both sides. After the military coup of February 2021, the SVP called on its members no longer to work with any Burmese amber material that left the country after June 2017. Several specialist journals, among them Cretaceous Research and the Journal of Vertebrate Paleontology, have imposed formal embargoes. So anyone who, as a collector, buys Burmite buys not only a 99-million-year-old piece of Earth's history but also an ethical position. Pre-2017 provenance with unbroken documentation can be defended. Anonymous pieces on Chinese platforms are a problem. At bernsteinmobil we do not appraise Burmite as a matter of principle, and we advise collectors to ask the question of origin before every purchase.

How to tell the three apart: fauna, spectrum, colour.

Anyone holding a piece and not immediately knowing where it comes from has three diagnostic tools. The simplest is the fauna itself. A non-biting midge (Chironomidae), a small orb-weaver, an ichneumon wasp: with overwhelming probability Baltic. A Mastotermes termite, an Anolis section, a bright red beetle elytron in honey-clear material: Dominican. A theropod feather, a toothed bird nestling, a snake in deep red, streaky resin: Burmese. This rule of thumb does not work in every single case, but in the experience of the Hamburg and Palanga curators it covers around 90 per cent of practice. The faunas are spread so far apart through geological time that they overlap at only a few points.

The second test is the FTIR spectrum, that is, Fourier-transform infrared spectroscopy. It is non-destructive and available in every mineralogical laboratory. Baltic succinite shows the typical Baltic shoulder in the 1250 to 1175 cm⁻¹ range, an absorption signature of the succinic-acid ester chemistry of the Eocene source material (Beck 1965, supplemented by Wagner-Wysiecka 2014). Dominican material from Hymenaea does not show this shoulder, but instead sharper bands around 888 cm⁻¹ from exomethylene groups of the sesquiterpenoids. Burmite resembles the Araucariaceae resins more closely in spectroscopic terms and has its own pattern with characteristic bands around 975 and 1645 cm⁻¹. Anyone who trades in or collects amber seriously should once have the spectra of their own pieces recorded; that costs around 80 to 150 euros per sample and saves a great deal of later discussion.

Third, colour and clarity. Baltic amber is mostly honey-yellow to brownish-yellow, often with whitish cloudiness (bone amber, caused by microscopic gas bubbles). Dominican material is clearer, more glass-like, with a spectrum from pale yellow to deep wine-red, plus the blue-fluorescing varieties of the Cordillera Septentrional. Burmite is deep red-brown to cherry-coloured, often with conspicuous flow streaks and stress cracks from the tectonic strain in the Kachin Basin. An experienced amber buyer usually recognises the three provenances from the first metre of cabinet distance. The certainty comes with practice. If you are unsure, the simplest route is to send a photo and a description of the fauna to a specialist museum or to us. A provenance assessment is part of the standard of every reputable appraisal and often decides three- to four-figure price differences.

Detecting fakes and manipulations.

The market values of genuine inclusion pieces have, over decades, produced a flourishing trade in imitations. The range runs from crude synthetic-resin fakes, which any collector recognises after handling a few pieces, to highly sophisticated manipulations in which genuine amber material is rebuilt into a carrier matrix for modern insects. A systematic overview helps to give the field some structure.

Pure synthetic-resin imitations.

Polyester, epoxy resin, occasionally polystyrene or acrylic glass, cast around an embedded insect (often freshly killed or already prepared). Distinguishing features: absent UV fluorescence or an anomalous fluorescence colour (genuine Baltic amber shows a characteristically pale-blue to light-yellow fluorescence under long-wave UV, depending on its weathering state). The smell test after heating a needle tip: genuine material releases aromatic terpene scents, while synthetic resin gives off a pungent solvent smell. Important: the hot-needle test is destructive and should only be applied to an inconspicuous spot and only to pieces worth under about 200 euros; on collector pieces it leaves a visible melt mark. A non-destructive quick test is the hot-car sun smell test: leave the piece on the centre console of a heated car for 20 to 30 minutes, then smell it. Genuine Baltic succinite gives off a faintly resinous, incense-like scent, while synthetic resin gives nothing or a weak solvent note. Hardness test: synthetic resin is usually softer and can be scratched at the surface with a steel needle. Density (salt-water test): Baltic amber has a density of about 1.05 to 1.10 g/cm³ and floats in saturated salt solution (density about 1.20 g/cm³), whereas most synthetic resins sink.

Copal with modern insects.

Considerably more insidious. Copal (young tree resin that is not yet fully polymerised, from African or Colombian sources) looks superficially like amber, is mouldable when warm and takes embedded recent insects in a deceptively convincing way. Many "amber inclusions" from tourist markets in South-East Asia or Latin America are exactly this. Distinguishing features: copal is noticeably softer (Mohs hardness 1.5–2 against 2–2.5 for genuine Baltic amber), partly dissolves in acetone or ethanol (genuine amber does not), and shows no pronounced succinic-acid band in the FTIR spectrum. A practical acetone-cotton-bud test: press a cotton bud soaked in acetone onto an inconspicuous spot for 30 seconds, then wipe with a white cloth. Copal leaves a sticky film and turns milky at the surface, whereas Baltic amber stays unchanged. Important: the enclosed insect is often a modern species whose systematic identification immediately exposes the swindle; a classic recent house fly has no business in the Eocene.

Hot-pressed and manipulated pieces.

The most demanding faking method: genuine amber dust or small genuine amber fragments are fused under pressure and temperature (typically 150–220 °C at 200–500 bar) into larger blocks, with embedded insects posing as an "inclusion". The result consists of genuine amber material and would pass every standard chemical test. Distinguishing features: characteristic streak and swirl structures under polarised light that go back to the pressing process (visible even without a polarising microscope, as a restless rotating pattern when you slowly turn the piece under a strong magnifier in raking light); the enclosed insect often shows untypical positional relationships (placed too centrally, arranged too "aesthetically"); the typical multi-phase resin-flow lines around the inclusion are missing, because it was never naturally enveloped. This technique was developed in Soviet and East German amber as the pressed-amber process without fraudulent intent. As an inclusion fake, however, it is now widely misused. Related, but technically different, is Polybern, a composite material of amber dust and synthetic resin that was common in manufactory-historical chains from the 1960s to the 1980s. Polybern was only rarely made with embedded inclusions, but it remains an important material category for collectors.

The "decay halo": what it really is.

Around many genuine inclusions there lies a milky, veil-like zone in the surrounding amber, popularly called a "decay cloud". It is diagnostically valuable, but misunderstood. In the case of the inclusion, it is not a trace of genuine decay; that would be incompatible with the anoxic preservation logic of amber. It is instead a diffusion zone in which water or other small molecules migrated out of the animal's body into the surrounding polymer and produced subtle cloudiness there over millions of years. Genuine inclusions show this zone, artificial ones almost never, because hot-pressing or casting produces no comparable long-term diffusion. So if you find a faint veil around an insect under the microscope, you should be pleased, not annoyed.

FTIR spectroscopy as the gold standard.

The most reliable authenticity test is Fourier-transform infrared spectroscopy. As early as 1965, Beck showed that Baltic succinite has a characteristic absorption band between 1175 and 1250 cm⁻¹, the so-called "Baltic shoulder", caused by the succinic-acid component. Other natural resins (Romanian rumanite, Sicilian simetite, Dominican amber) do not show this signature, or only in weakened form; synthetic resins are immediately recognisable as artificial under spectroscopy. An FTIR measurement takes a few minutes, is non-destructive and is regarded as the definitive method of proof. In Germany, an FTIR analysis can in practice be commissioned at the Senckenberg Research Institute in Frankfurt, at the Mineralogical-Petrographic Institute of the University of Hamburg, or at the German Research Centre for Geosciences (GFZ) in Potsdam; the cost ranges, depending on the effort involved, from about 80 to 250 euros per piece.

Once spectroscopy has confirmed that the piece is genuine, the second question begins, and in most cases the harder one: what is it worth?

Market valuation of inclusion pieces.

The price of an inclusion is a complex function of how rare the animal group is, completeness and quality of preservation, clarity of the surrounding amber, the size of the piece, scientific significance and, not least, the swings of the collector market. The overview below is a rough guide for Baltic material in medium to good quality. Top prices for individual pieces can exceed these ranges by one or two orders of magnitude.

A rule of thumb among collectors runs: scientific value and aesthetic value need not coincide. A tiny, unremarkable piece with a pseudoscorpion clinging to a midge's palp can be a scientific key specimen and command a price to match, while an optically impressive beetle inclusion in a large clear piece is more valuable to a collector yet tells science nothing further. The two value scales follow different logics, and shrewd collectors know both.

Anyone who can photograph their piece has already negotiated half the price.

The same image lands in our inbox every week. A smartphone snapshot under a kitchen lamp, yellowish, crooked, the inclusion a brown dot in an amber haze. With it, the question: "What is this worth?" The honest answer is then almost always the same: not assessable from this photo. A serious online appraisal lives on the quality of the images. With ten minutes of patience, a sheet of black card and the daylight at your window, the same piece of amber turns into a documentable collector's item. This section shows you how to turn a button in your hand into an assessable file.

The light decides before the shutter clicks.

Amber is an optically tricky material. Succinite is transparent but not clear like glass. It refracts light at a refractive index of about 1.54, scatters it, reflects it, and any light source with the wrong colour temperature tints the material in a direction that falsifies its true honey tone. Anyone who wants to photograph an inclusion therefore starts not with the camera but with the light. Daylight is the gold standard. Midday, under light cloud, at the window, with no direct sunlight. The cloud cover acts like a giant softbox and delivers exactly that even, low-shadow illumination of around 5,500 to 6,500 kelvin that lifts the inclusion out of the material haze.

Anyone forced to work in the evening reaches for LED lamps with a colour temperature of 5,000 to 6,000 kelvin. That is neutral to cool white, not cosy living-room light. Halogen lamps (around 3,000 K), incandescent bulbs (2,700 K) and warm-white desk lamps give the amber an orange cast that distorts any colour judgement. Two light sources are ideal, one to the side at a 45-degree angle, one at an angle from above. This classic studio arrangement creates modelling instead of a flat front, and the inclusion gains depth.

A practical note from our consulting work: the smartphone flash is off limits. It sits a few millimetres beside the lens, produces a white reflective spot directly on the amber surface and kills all the fine depth structures. If you have no good light at home, take the amber somewhere else rather than working with flash. The piece is not going anywhere; the photo opportunity is.

Scale, background, clear view: the setup.

Once the light is set, the stage comes next. Background: black craft card, matt, without sheen. With very dark or whitish-cloudy amber (bone amber), white card works better. Checked oilcloth covers, wood grain, the patterned sofa are assessment killers. They drag the eye away from the inclusion and make on-screen colour correction impossible. An A4 sheet for seven cents does this job reliably.

A scale always belongs next to the piece. A ruler with millimetre markings, a one-euro coin (23.25 mm diameter, a convention of the European Central Bank), a match of known length. Without a size reference the inclusion cannot be judged, and our appraisal becomes speculation. A midge can look on a photo like a two-millimetre non-biting midge (Chironomidae) or like an eight-millimetre mosquito (Culicidae), and the price difference is a factor of three to five.

The piece itself must lie clear. No setting, no chain, no fabric pouch. If the amber is set as a pendant and the inclusion partly disappears under the gold setting, it cannot be assessed. In that case: turn the piece so that the inclusion stands completely clear from above or the side, and supply several shots from the unobstructed angles. An inclusion that is only half visible halves the estimated value.

A professional trick that immediately improves most inclusions by one visibility class: a drop of cooking oil or a drop of water on the amber surface, directly over the inclusion. Refractive-index matching works here: amber sits at n=1.54, cooking oil at around 1.47, water at 1.33. Both are far closer to amber than air at 1.00. Disruptive surface reflections vanish and the inclusion stands out in relief. Baltic succinite is insensitive to water and cooking oil; the piece takes no harm (Weitschat and Wichard 2002, p. 18).

Macro, angle, video: what we really need to see.

Most inclusions are small. Two to five millimetres of body length is standard for the most common Diptera inclusions, which make up around 55 to 70 per cent of all animal inclusions in Baltic amber (Weitschat and Wichard 2002). On a normal smartphone shot from twenty centimetres away, a three-millimetre midge is a brown streak. Anyone who wants a serious appraisal has to move into the macro range. Current mid-range and high-end smartphones have a macro mode that focuses from about two to three centimetres away. That is enough for a first assessment. Anyone who photographs inclusions more often buys a clip-on macro lens with tenfold to twentyfold magnification for 30 to 60 euros. That is the best investment an amber owner can make in this price range.

At least three angles, ideally five. A top view onto the largest amber face, a side view to judge the thickness of the piece and the three-dimensional position of the inclusion, an oblique view. Inclusions look completely different from different angles. A spider (Araneae) from above looks like a dot with lines; the same spider from the side suddenly shows the eight legs in their natural arrangement together with the two-part body of prosoma and opisthosoma. A midge can appear obscured from one angle and clearly legible from the next.

If you can, shoot a short video. Ten to twenty seconds, the piece turned slowly under constant light, with as steady a hand as possible or the coin turned on the table. A video like this shows us the spatial position of the inclusion better than ten stills, and we recognise at once whether the inclusion is genuinely embedded (with accompanying gas bubbles and flow marks in the surrounding resin) or lies on a cut plane, a classic forgery indicator in inserted copal fabrications (Grimaldi and Engel 2005). WhatsApp and email accept videos up to 100 megabytes without trouble, which is several times more than enough for this purpose.

The full checklist for an assessable enquiry consists of six mandatory shots and a bonus step. Mandatory: first, an overall view with scale; second, a top view of the inclusion filling the frame; third, a side view; fourth, a macro detail of the inclusion; fifth, a reverse or unpolished surface shot; sixth, the weight on a letter scale in grams (accurate to 0.1 g). Bonus step for collectors with a UV lamp (365 to 395 nanometres, about 15 to 25 euros by mail order): an additional shot under UV. The characteristic milky-blue to greenish-blue surface fluorescence of Baltic succinite is one of the fastest authenticity markers (Penney 2010). Quick decision guide: if the inclusion is smaller than 2 mm, the macro lens is mandatory. If the piece sits in a jewellery setting, the inclusion must be photographed as freely visible as possible for a serious appraisal. If only a smartphone without macro mode is available, the six mandatory shots are the absolute minimum, without which a reliable estimate is barely possible.

What I read from your photos.

Good photo documentation is not an end in itself. It is the basis of an assessment in four dimensions that I go through with every enquiry. First: what is the inclusion? On a sharp macro shot I can usually recognise the animal group, often the family too. Long feathered antennae plus two wings plus a slender body point to a male non-biting midge (Chironomidae). Eight legs plus a two-part body plus chelicerae mean a spider (Araneae). A hard glossy body with elytra is a beetle (Coleoptera). This initial classification steers the value range from around 20 to 50 euros per piece for clear non-biting midges up well into the four-figure range for beetles or complete spiders.

Second: which provenance? Clear, honey-yellow material with characteristic Baltic UV fluorescence and an Eocene faunal assemblage (44 to 49 million years, Lutetian) points to succinite from Kaliningrad, Poland or Lithuania. Glass-clear, reddish material with a Miocene inclusion fauna suggests Dominican amber from the La Toca or Yanigua formation, 16 to 20 million years old, source tree Hymenaea protera. Red-brown, somewhat cloudier material with Cretaceous inclusions is Burmese burmite from the Hukawng Valley, around 99 million years, with all the ethical reservations that the material has carried since the military coup of 2021. Provenance doubles or halves the value.

Third: authenticity indicators. Does the inclusion sit embedded three-dimensionally, with accompanying gas bubbles and flow marks in the surrounding resin, or does it lie on a cut plane with a recognisable glue-seam zone (typical of copal fabrications from Madagascar or Colombia)? Does the material show Baltic UV fluorescence in the 365 to 395 nm range, or is it chemically cold? From the photos one can often derive a probability of authenticity, in the order of 80 to 95 per cent. Some residual uncertainty always remains; it can only be resolved in the hand with a hot-needle or salt-water test.

Fourth: market value. From inclusion type, preservation, clarity, weight, cut and provenance comes a concrete value range in euros per piece. We always communicate a range, not a single figure, because the amber market fluctuates regionally (the German domestic market sober, the Asian market with a markup of factor 3 to 10) and the final return depends on the route of sale. We send this assessment back to you in writing, usually within two to three working days.

Sending an enquiry: WhatsApp or email, three steps.

Once your photos are ready, three steps lead to the appraisal enquiry. First: load the images and any video onto your smartphone. Second: choose a contact route. WhatsApp on 0176–60926047 is the fastest channel for images, and Marcel usually replies within a few hours. Anyone who prefers to work documentarily or sends more than ten images uses info@bernsteinmobil.de. Third: write a short accompanying note. Origin of the piece (inherited, bought, beach find from Usedom or Hiddensee), weight in grams, the visible inclusion as you see it, the desired depth of appraisal.

The photo appraisal costs between 30 and 80 euros per piece, depending on the research effort. A simple non-biting midge in clear Baltic succinite is covered by the basic flat rate. An unusual spider with a prey scene in fossil spinning thread, a presumed vertebrate fragment or a piece with provenance uncertainties costs more, because the research takes longer and external specialists may need to be consulted (for example at the Geological-Palaeontological Institute Hamburg or the Amber Museum Palanga). We name the final price before the appraisal; nobody is surprised by an invoice.

For pieces from an estimated value of around 2,000 euros, we recommend a personal examination after the photo pre-check, either through a visit to a specialist museum (Geological-Palaeontological Institute Hamburg, Amber Museum Palanga, German Amber Museum Ribnitz-Damgarten) or through a sworn expert. We arrange contact with qualified appraisers in northern Germany and Poland and prepare the documents. A photo appraisal is a good start, but for genuinely valuable pieces it does not replace examination in the hand.

A final remark. We appraise Baltic amber only, that is succinite from the classic Eocene deposits of the Lutetian. We take note of Dominican, Mexican and Burmese pieces, but for these provenances we refer you on to specialist appraisers, because only someone who works with the material daily should name a serious market value. Anyone who owns a Baltic piece and wants to know what it is worth has come to the right place. We look forward to your photos.

Coda: from everyday appraisal practice, and sources.

One Tuesday morning in February 2026 a small cardboard box sat on my desk, cotton wool inside and a piece of amber within it, sent by a widow from Krefeld. Her husband, who died in 2024, had bought the piece in 1978 at a backyard market in Gdańsk for 40 Deutschmarks. She wanted to know whether it was worth anything. It was a spider, barely four millimetres in body length, all eight legs intact, with two thread fragments of a fossil web beside it. The elongated, long-legged habit and the fine silk threads pointed to a member of the Linyphiidae, the sheet-weavers, which are already well documented in the Eocene. I gave her a figure of 1,400 euros, subject to examination in the hand. Mornings like that are the reason this page exists.

What actually lands on the desk every day.

The enquiries that come in through the appraisal form follow a distribution I could predict in my sleep after roughly a decade of consulting. About seventy per cent are small Baltic pieces with non-biting midges (Chironomidae), dark-winged fungus gnats (Sciaridae) or gall midges (Cecidomyiidae), mostly two to four millimetres in body length, in middling clarity. This distribution matches the dominance of Diptera that Weitschat & Wichard give in their 2002 Atlas of Plants and Animals in Baltic Amber, at around 55 per cent of all animal inclusions. The typical value range lies between 80 and 400 euros. The owners inherited the piece, found it on the beach, or bought it years ago at a Polish market. They are not rarely taken aback to learn that the gnat is not worth 5,000 euros.

About twenty per cent of the pieces sit above that, sometimes well above. Spiders (Araneae, often Linyphiidae or Theridiidae), beetles (above all Curculionidae and Staphylinidae), ant groups (Formicidae of the genera Yantaromyrmex, Ctenobethylus, Lasius), occasionally a small solitary bee with intact membranous wings. Here the appraisal gets interesting, because it swings between 500 and 5,000 euros and depends on the cut, on the viewing axis, and on the surrounding material. These pieces are often misjudged, in both directions.

About two per cent are fakes. Usually copal from Madagascar (Hymenaea verrucosa, a few thousand to a few million years old) with a modern house spider inserted, occasionally polyester imitations of Chinese manufacture with well-placed insects. The frequency has risen sharply since 2021, in step with the shift of the amber trade onto online marketplaces with no physical examination. Penney already documented Madagascar copal as the most common fake material in the European market in 2010 (Biodiversity of Fossils in Amber).

Genuine sensations, that is vertebrate fragments, complete butterflies (Lepidoptera, fewer than 200 scientifically published specimens in the Baltic material), behavioural scenes with more than three actors, cross the desk perhaps once or twice a year. One of them came in November 2025: a small lizard foot in Baltic material (Squamata, family still open), submitted from an estate in Lübeck. The piece is now at the Geological-Palaeontological Institute in Hamburg for further study, and the seller received a brokered price in the low five figures.

The five most common misconceptions.

First and by far the most frequent: the assumption that every inclusion is museum-grade. It usually sounds like this: "I have a gnat in amber, surely it must be worth many thousands of euros." It is not. An average non-biting midge (Chironomidae) in a clear Baltic piece is the most common inclusion type of all, with a share of about 30 per cent of all Diptera inclusions according to Krzemiński & Krzemińska 2003 (Acta zoologica cracoviensia), and sits in the German collector market typically at 5 to 20 euros per piece. That is collector stock, not display material for the natural history museum.

Second: confusing natural amber with inclusion amber. Many enquiries arrive with the expectation that a large, heavy piece of natural amber must be especially valuable because it is old and unworked. Natural amber without an inclusion costs between 0.50 and 5 euros per gram in the German collector market from 2024 to 2026. A twenty-gram lump from the beach is therefore worth perhaps 30 euros, not 3,000.

Third: trust in polyester imitations. Several times a month I receive photographs of supposed scorpions, lizards, even a bird's head on one occasion, which the owner bought at a weekly market or on holiday in Poland for 200 to 500 euros. The material is usually synthetic resin, recognisable by the hot-needle test (acrid chemical smell instead of resinous, incense-like) and by the UV test (no milky-blue surface fluorescence at 365 nanometres, which is characteristic of succinite). The scorpion is usually a modern juvenile scorpion from Vietnamese dried-specimen production. Replacement value: nil.

Fourth: the assumption that dark or red amber is generally more valuable. The colour is primarily an oxidation feature, not a value criterion. It tells you something about the storage history of the piece, that is oxygen exposure and UV action over millennia, nothing about the inclusion within it. In the Chinese market red amber is indeed traded at a premium, but that is a market phenomenon, not a materials-science one.

Fifth: the hope for dinosaur DNA. It comes up less often than it used to, but it still comes up. Jurassic Park is a good film and a scientifically refuted hypothesis. Allentoft et al. demonstrated a DNA half-life of around 521 years in 2012 in Proceedings of the Royal Society B, which places even the youngest Dominican ambers (16 to 20 million years) far beyond any threshold of legibility. Anyone who wants to sell the piece on that basis should not overstretch the myth.

My own favourites.

When I am asked which inclusion pieces still hold my interest after years, I name three categories that have little to do with one another. First: small ant groups. Three, four, five animals in the same piece, often in different poses, one walking, one scratching itself, one already half stiffened. Such inclusions are snapshots of social behaviour, frozen around 44 million years ago in the Middle Eocene (Lutetian). I own a small piece myself with seven workers of a Yantaromyrmex species, described by Dlussky, Radchenko & Dubovikoff 2014, which I will never sell.

Second: plant inclusions. Above all three-dimensionally preserved leaf fragments with recognisable venation and toothing, occasionally with small aphid colonies (Aphidoidea) on them. Such pieces are undervalued in the market, because collectors want animals, not botany. For me they are the most honest records of the Eocene amber forest. A Magnoliaceae bud in a clear piece, which I saw in 2019 at the Amber Museum in Gdańsk, stayed with me for months. Sadowski et al. documented a whole series of such plant inclusions in 2017 in Earth-Science Reviews, along with their palaeoecological value for the source-tree debate.

Third: pieces cut in the Königsberg workshop tradition. When a Baltic inclusion sits in a piece that was cut in the 1920s or 1930s at the State Amber Manufactory, two stories of value come together. The inclusion piece itself, and the manufactory-historical context. Such pieces have become rare, because many Königsberg holdings were lost in the war or scattered through private collections.

What all three categories share: they are not the most expensive pieces I have held. They are the ones that tell you something. A Dominican Anolis fragment for 80,000 euros is impressive. An Eocene ant colony for 1,200 euros is history.

A Dominican Anolis fragment for 80,000 euros is impressive. An Eocene ant colony for 1,200 euros is history.

Practical tips that appear in no table.

Inherited inclusions are often worth more than the heirs suspect, because they were bought on the collector markets of the seventies and eighties, when prices were low and good pieces common. A spider in Baltic amber that the grandfather bought in Gdańsk in 1975 for 30 marks is today often worth 600 to 1,500 euros, and more with good clarity and complete leg preservation. Do not throw anything away without looking at it once.

Natural ambers from the beach, for example from Usedom, Hiddensee or the Curonian Spit, occasionally contain inclusions, but mostly very small and hard-to-see ones, because the tumbling motion in the surf rounds off the outer layers of the pieces and often destroys inclusions at the edge. A found beach amber with a recognisable gnat is a considerable rarity and should be examined professionally at once, because such finds are worth documenting. The State Office for Culture and Monument Preservation of Mecklenburg-Vorpommern in Schwerin accepts reports of such finds.

A piece with a good inclusion that sits in a jewellery setting often loses value, because the setting devalues the material instead of enhancing it. Anyone who has a valuable inclusion should not have it reworked into jewellery, but leave it as a study object. If the piece is already mounted, the amber core can often be released from the setting without damage, which restores the value to collector level. With a Mohs hardness of 2 to 2.5 amber is soft and must be handled carefully when prised out of claw settings.

Insurance: inclusion pieces over about 2,000 euros should be included separately in household contents insurance, with photographic documentation and a written appraisal from a recognised expert. It is important to check the valuables clause of your own policy: many contents policies cover collectibles only up to 20 per cent of the sum insured, or not at all. For higher values a separate collector's insurance is worthwhile (for example through Allianz, Mannheimer or Helvetia). The appraisal usually costs 50 to 150 euros and is worth the investment; without documentation insurers in the event of a claim often pay only the material value, that is the basic amber price without the inclusion premium.

Selling: the best route for good inclusion pieces rarely runs through eBay or general marketplaces, but through specialist auction houses (Heritage Auctions in Dallas, Aguttes in Paris, Quittenbaum in Munich, Hermann Historica in Grasbrunn, Henry's in Mutterstadt), amber trade fairs such as the Munich Mineral Show, or direct sale to museums. Anyone who sells on the general private market often achieves only half the collector value.

When you think you are holding a sensation.

It happens. A collector from the north German coast, a beachcombing enthusiast from former East Prussia, the heir to a grandfather's collection looks more closely at a piece and believes they see something unusual. A small lizard. A complete feather. A vertebrate fragment that does not fit morphologically into the usual beetle-midge-spider trio. Before ringing the local press or an auction house, a few steps are advisable, and their order matters more than their content.

First: do not clean, do not polish, do not open. Any mechanical treatment of a potentially scientifically important piece can cause irreversible damage. The temptation to clear a cloudy surface with sandpaper is enormous and exactly wrong. The piece should be left untouched.

Second: document it. High-resolution photographs from several angles, with a scale alongside (a coin or a ruler), and where possible under different lighting conditions: reflected light, transmitted light, oblique illumination. Anyone who owns a stereo microscope, or has access to one, should also take detailed micrographs.

Third: make first contact with a specialist institution. The first points of contact for a German amber find are the Geoscience Centre of the University of Göttingen, the Senckenberg Research Institute in Frankfurt, the Geological-Palaeontological Museum in Hamburg, or the Museum für Naturkunde in Berlin. A plain email with the photograph and a brief account of the circumstances of the find is the right approach. In practice the institutes respond promptly, because they have an interest in examining potentially important pieces before they disappear onto the open market.

Fourth: document ownership and provenance. Who acquired the piece, and when, where and how, is relevant to the scientific work, both legally and for assessing authenticity. Beach finds on German Baltic coasts may generally be collected freely; material from archaeological contexts, or from countries with restrictive amber legislation (Poland, Lithuania), is subject to different rules.

In the case of a genuinely important piece, the institutes will usually offer to work the material up scientifically in return for an expense allowance or a long-term loan agreement. Some collectors prefer to keep the piece in private hands with a documented scientific description; others hand it over permanently. Both routes are legitimate. The wrong route is to go straight to the auction market, because there the scientific assessment comes last (if at all) and the value is determined solely by aesthetic and narrative factors.

One last remark. Baltic amber is one of the richest palaeontological archives in the world, but it is finite. The productive "blue earth" of the Samland has been mined systematically for more than one hundred and fifty years; output is falling, prices are rising, and the importance of each individual piece worked up scientifically grows. Anyone holding a noteworthy piece is holding part of an archive that will be exhausted within a few generations. That awareness should shape how every genuine inclusion is handled, even and especially when it turns out to be just "another fungus gnat".

Sources and further reading.

• Allentoft, M. E., Collins, M., Harker, D., Haile, J., Oskam, C. L., Hale, M. L. et al. (2012): The half-life of DNA in bone: measuring decay kinetics in 158 dated fossils. Proceedings of the Royal Society B 279 (1748), pp. 4724–4733.
• Bachofen-Echt, A. (1949): Der Bernstein und seine Einschlüsse. Springer, Vienna. (Historical standard work; still useful factually, but produced within a scientific milieu of the 1920s to 1940s whose institutional entanglements and turns of phrase should be read today with historical distance.)
• Beck, C. W. (1965): The infrared spectra of amber and the identification of Baltic amber. Archaeometry 8 (1), pp. 96–109.
• Cano, R. J., Poinar, H. N., Pieniazek, N. J., Acra, A. & Poinar, G. O. (1993): Amplification and sequencing of DNA from a 120–135 million-year-old weevil. Nature 363, pp. 536–538.
• Conwentz, H. (1890): Monographie der baltischen Bernsteinbäume. Engelmann, Danzig.
• DeSalle, R., Gatesy, J., Wheeler, W. & Grimaldi, D. (1992): DNA sequences from a fossil termite in Oligo-Miocene amber and their phylogenetic implications. Science 257 (5078), pp. 1933–1936.
• Dlussky, G. M. (1997): Genera of ants (Hymenoptera: Formicidae) from Baltic amber. Paleontological Journal 31 (6), pp. 616–627.
• Dlussky, G. M., Radchenko, A. G. & Dubovikoff, D. A. (2014): A new species of the genus Yantaromyrmex (Hymenoptera, Formicidae) from late Eocene European amber. Annales Zoologici 64 (3), pp. 367–377.
• Henderickx, H. (2005): A new pseudoscorpion (Arachnida, Pseudoscorpiones) from Baltic amber. Phegea 33, pp. 25–28.
• Henwood, A. (1993): Recent plant resins and the taphonomy of organisms in amber: a review. Modern Geology 19, pp. 35–59.
• Hieke, F. & Pietrzeniuk, E. (1984): Die Bernstein-Käfer des Museums für Naturkunde, Berlin. Mitteilungen aus dem Zoologischen Museum Berlin 60 (2), pp. 297–326.
• Höss, M., Jaruga, P., Zastawny, T. H., Dizdaroglu, M. & Pääbo, S. (1996): DNA damage and DNA sequence retrieval from ancient tissues. Nucleic Acids Research 24 (7), pp. 1304–1307.
• Jefremow, I. A. (1940): Taphonomy: a new branch of paleontology. Pan-American Geologist 74, pp. 81–93.
• Klebs, R. (1910): Über Bernsteineinschlüsse im allgemeinen und die Coleopteren meiner Bernsteinsammlung. Schriften der Physikalisch-ökonomischen Gesellschaft zu Königsberg 51, pp. 217–242.
• Krumbiegel, G. & Krumbiegel, B. (1994): Bernstein, Fossile Harze aus aller Welt. Goldschneck-Verlag, Korb.
• Larsson, S. G. (1978): Baltic Amber, a Palaeobiological Study. Entomonograph Vol. 1, Scandinavian Science Press, Klampenborg.
• Martínez-Delclòs, X., Briggs, D. E. G. & Peñalver, E. (2004): Taphonomy of insects in carbonates and amber. Palaeogeography, Palaeoclimatology, Palaeoecology 203 (1–2), pp. 19–64.
• Mosbrugger, V., Utescher, T. & Dilcher, D. L. (2005): Cenozoic continental climatic evolution of Central Europe. Proceedings of the National Academy of Sciences USA 102 (42), pp. 14964–14969.
• Penney, D. (ed.) (2010): Biodiversity of Fossils in Amber from the Major World Deposits. Siri Scientific Press, Manchester.
• Penney, D., Wadsworth, C., Fox, G., Kennedy, S. L., Preziosi, R. F. & Brown, T. A. (2013): Absence of ancient DNA in sub-fossil insect inclusions preserved in "Anthropocene" Colombian copal. PLoS ONE 8 (9), e73150.
• Perrichot, V., Marion, L., Néraudeau, D., Vullo, R. & Tafforeau, P. (2008): The early evolution of feathers: fossil evidence from Cretaceous amber of France. Proceedings of the Royal Society B 275 (1639), pp. 1197–1202.
• Sadowski, E.-M., Schmidt, A. R., Seyfullah, L. J. & Kunzmann, L. (2017): Conifers of the "Baltic amber forest" and their palaeoecological significance. Earth-Science Reviews 172, pp. 1–43.
• Schmidt, A. R. & Dilcher, D. L. (2007): Aquatic organisms as amber inclusions and examples from a modern swamp forest. Proceedings of the National Academy of Sciences USA 104 (42), pp. 16581–16585.
• Seyfullah, L. J., Beimforde, C., Dal Corso, J., Perrichot, V., Rikkinen, J. & Schmidt, A. R. (2018): Production and preservation of resins, past and present. Biological Reviews 93 (3), pp. 1684–1714.
• Smith, C. I. & Austin, J. J. (2014): The Jurassic Park fantasy refuted: no DNA in amber-preserved insects. PLoS ONE 9 (10), comment on the Penney study.
• Sontag, E. (2003): Animal inclusions in a sample of unselected Baltic amber. Acta Zoologica Cracoviensia 46 (suppl.), pp. 431–440.
• Standke, G. (2008): Bitterfelder Bernstein gleich Baltischer Bernstein?, Eine geologische Raum-Zeit-Betrachtung und genetische Schlussfolgerungen. Exkursionsführer und Veröffentlichungen der Deutschen Gesellschaft für Geowissenschaften 236, pp. 11–33.
• Stankiewicz, B. A., Briggs, D. E. G., Michels, R., Collinson, M. E., Flannery, M. B. & Evershed, R. P. (1998): Alternative origin of aliphatic polymer in kerogen. Geology 26 (4), pp. 327–330.
• Wagner-Wysiecka, E. (2018): Infrared spectroscopy in studies of natural resins as a tool for amber provenance studies. Physical Sciences Reviews 3 (3), 20180004.
• Weitschat, W. & Wichard, W. (2002): Atlas der Pflanzen und Tiere im Baltischen Bernstein. Verlag Dr. Friedrich Pfeil, Munich (ISBN 978-3-89937-009-5).
• Wheeler, W. M. (1915): The ants of the Baltic amber. Schriften der Physikalisch-ökonomischen Gesellschaft zu Königsberg 55, pp. 1–142.
• Wolfe, A. P., Tappert, R., Muehlenbachs, K., Boudreau, M., McKellar, R. C., Basinger, J. F. & Garrett, A. (2009): A new proposal concerning the botanical origin of Baltic amber. Proceedings of the Royal Society B 276 (1672), pp. 3403–3412.
• Wunderlich, J. (2004): Fossil spiders in amber and copal. Beiträge zur Araneologie 3 (A+B), self-published, Hirschberg.
• Wunderlich, J. (2008): Fossil and extant spiders (Araneae). Beiträge zur Araneologie 5, self-published, Hirschberg.