About Amber and its Simulants Amber is formed from the resin of coniferous trees from at least 40 million years ago. This fossilized resin was often transported over long distances through glacial action, to reach various places in Poland, Belarus, Lithuania, Latvia and Germany. It even travelled as far as the eastern shores of the British Isles, to Jutland and southern shores of Scandinavia.
The fossil beaches of the Baltic Sea are often erroneously associated with the origin of Amber, but they are in fact the final stop in the materials long journey.
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| Forms, Colours and Inclusions Baltic Amber is divided into two groups of materials called primary and secondary Amber. The primary varieties are further subdivided based on their internal structure. It is this structure that determines the transparency and colour of the material and is largely dependent on the number and arrangement of gas bubbles trapped inside each piece. Primary varieties include: transparent Amber; translucent Amber; opaque yellow Amber and finally opaque white Amber, in which the internal structure is that of a solid foam.
Another group of primary varieties includes Amber 'polluted' with organic substance and wood chips. This variety is called "earth" though it has nothing to do with soil. Earth Amber often contains numerous gas bubbles formed during decomposition; it may also contain plant and animal inclusions.
The primary varieties of Amber are not durable and under the effect of air, light, humidity fluctuations and temperature variations they change their colour and internal structure and are transformed into secondary varieties. The yellow colour changes into red or orange and the internal structure is characterised by numerous cracks, known as "sugar" structure. The most eroded Amber pieces are those that remain in the soil, above ground water level, for a long time. Amber exposed to air and light changes colour over time; from yellow to red or orange and from white to yellow.
Amber is known for its inclusions, which are mainly organic. Whole lichens, liverworts or mosses and larger plant fragments, such as flowers, fruits, seeds, needles, leaves or twigs have been seen in pieces of Amber. The most often encountered inclusions are small fragments of plant tissue, but these are often impossible to identify. The most common impurities in Baltic Amber are stellate hairs from scales that protect oak buds. |
| Insect inclusion in Baltic Amber The most exciting inclusions are animals embedded in Amber, mostly small arthropods. Over 2,600 species have been identified including: ants, arachnids walking or hunting on trunks of resin-producing trees, dipterans flying nearby, hymenopterans, caddis flies or millipedes foraging on the forest floor, which were embedded in these mortal traps. Their tissues were mummified in a dehydrating environment, or they were impregnated with resin.
Vertebrates from the Amber forest have also left their mark in Amber. Four lizards of the genus Nucras, at present inhabiting southern Africa, have been found embedded in Amber pieces. The surface of some Amber samples even bear the prints of mammal paws, their presence in the Amber forest also indicated by the inclusion of their parasites - fleas, ticks and blood-sucking insects (e.g. mosquitoes), or mammal hairs, embedded in Amber pieces. |
| Simulants Fake Amber is not hard to make and often difficult to detect. There is also the common practice of forging Amber inclusions to make pieces more desirable. As the British Museum of Natural History discovered when one of their scientists found a falsification in their collection. A very well preserved fly was described as "a palaeontological rarity". However, someone had divided the piece and carved a concave hole, into which they then placed the fly before covering it with an "Amber like" material and gluing the two halves together again!
Forged insect inclusions aside, there are two common Amber simulants: Copal and Plastic.
Copal
Before artificial resins became available, imitation Amber was made of copal, a natural subfossil resin, found in abundance in the Southern Hemisphere (e.g. Brazil, Africa and Colombia). Though copal often contains natural organic inclusions, additional inclusions are often artificially embedded in it.
Copal, which is tree resin that has not yet fully fossilised to Amber, may be anything up 3-4 million years old and debate still rages over certain Kenyan and South American deposits, as to whether they should be called Copal or Amber. Given the right conditions, Copal will eventually become Amber.
Copal has a less robust structure than Amber and can be more easily dissolved with solvents. It also has a slightly lower specific gravity or density, but it shares many other characteristics with true Amber.
Plastic
A wide variety of coloured plastics have been used to fake Amber over the years and the more modern materials can sometimes be difficult to tell from the real thing. Often the only way to identify the various materials is by destructive or laboratory testing. The most usual test is to burn a small area of the 'Amber' with a hot pin and try to differentiate between the resinous pine small of real Amber and the acrid smell of plastic.
Re-constituted Amber
Although not strictly an imitation, many modern Amber pieces have been re-processed by manufacturers who heat the material in autoclaves. They do this in order to change the shape, size, or colour of the pieces and reduce wastage. |
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