Amber: the Jurassic gem
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Dinosaurs have been more popular than ever since their starring role in the film Jurassic Park. A more surprising result of the film's popularity has been a worldwide surge in demand for amber jewellery. Millions of people learned from the film that amber, which is fossilised pine tree resin, is ancient and valuable, like an antique from history. While amber's use in adornment is probably as old as mankind itself, in recent times it has had a limited market. Of course, that was before everyone saw dinosaur DNA extracted from a mosquito trapped in amber in the film. Since the screening of Jurassic Park interest in the mineral amber has grown significantly. Demand is especially strong for amber with insects inside it. Unfortunately this has increased the quantity of fake amber coming on to the market. Some of these pieces have insect inclusions skillfully placed in the body of the matrix.
The British Natural History Museum recently discovered that a fly preserved in amber thought to be one of the oldest known examples of this particular species was in fact a fake and probably no more than 150 years old. (More of this fly later). Evidence of this nature, that even the best can be fooled should alert all collectors to the possibility of being misled or simply cheated.
"Amber is like a time capsule made and placed in the earth by nature herself," said David Federman, author of the Consumer Guide to Colored Gemstones. "It has helped paleontologists reconstruct life on earth in its primal phases. More than 1,000 extinct species of insects have been identified in amber."
Made by the sun
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"Stone Age man imbued amber with supernatural properties and used it to wear and to worship," says Mr Federman. "Amber took on great value and significance to, among others, the Assyrians, Egyptians, Etruscans, Phoenicians and Greeks. It never completely went out of vogue since the Stone Age. Between 1895 and 1900, one million kilograms of Baltic amber were produced for jewelry."
There are many myths surrounding the origin of amber. Ovid wrote that when Phaethon, a son of Helios, the sun, convinced his father to allow him to drive the chariot of the sun through the heavens for a day, he erred too close to the earth, scorching it. To save the earth, Zeus struck Phaethon with a thunderbolt and he died, plunging out of the sky. His mother and sister turned into trees in their grief but still mourned him. Their tears, dried by the sun, are amber.
The Greeks called amber 'elektron', sun-made, perhaps because of this story, or perhaps because it becomes electrically charged when rubbed with a cloth and can attract small particles. Homer mentions amber jewellery - earrings and a necklace of amber beads - as a princely gift in the Odyssey.
Another ancient writer, Nicias, said that amber was the juice or essence of the setting sun congealed in the sea and cast up on the shore.
The Romans sent armies to conquer and control amber-producing areas. The Emperor Nero was a great connoisseur of amber. During his time, according to the Roman historian Pliny, the price of an amber figurine, no matter how small, exceeded the price of a healthy slave.
The ancient Germans burned amber as incense, so they called it 'bernstein', or 'burn stone'. Clear colourless amber was considered the best material for rosary beads in the Middle Ages on account of its smooth silky feel. Certain orders of knights controlled the trade, and unauthorised possession of raw amber was illegal in most of Europe by the year 1400.
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What secrets might amber hold?
So could a mosquito trapped in amber really contain dinosaur DNA? Most amber just isn't old enough, having had some 25 to 50 million birthdays at the most. The dinosaurs died out 65 million years ago at the end of the Cretaceous Period. The Jurassic period was 144 million years ago.
Determining Authenticity
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If the British Museum can be fooled into purchasing a piece of fake amber how can we as non-specialist jewelry buyers be sure we are getting the real thing. A common fake is copal or ‘modern amber’. In some case copal, which is tree resin which has not yet fully fossilised to amber and may be anything up 3-4 million years old is described as true amber. Debate still rages in the UK about certain Kenyan deposits as to whether they should be called copal or amber and I have heard of similar arguments concerning deposits found in South America.
Here are ten simple do-it-yourself, do-at-home tests that you can do to determine if your piece is genuine or not as explained by Garry Platt. More sophisticated and complex tests are possible but they require access to laboratory equipment. These more complex tests include Refraction Index, Precise Specific Gravity and Melting Point.
When examining a specimen you should try at least 3 of the following methods detailed here. If the item in question fails any one of the tests, it could well mean the piece is not true amber.
(Test 1) HARDNESS.
Amber has hardness on Moh’s scale in the region of 2 - 3. Using appropriate scratch sticks it should be reasonably straightforward to test the sample under question.
(Test 2) HOT NEEDLE.
Heat a needlepoint in a flame until glowing red and then push the point into the sample for testing. With copal the needle melts the material quicker than amber and omits a light fragrant odour. Amber when tested does not melt as quickly as the copal and omits sooty fumes.
(Test 3) SOLUBILITY.
Copal will dissolve in acetone. This test can be done by dispensing the acetone from an eyedropper onto a clean surface of the test specimen. Place one drop on the surface of the test piece and allow to evaporate, then place a second drop on the same area. Copal will become tacky; amber will remain unaffected by contact with acetone.
(Test 4) UV
Copal under a short-wave UV light shows hardly any colour change. Amber fluoresces a pale shade of blue.
(Test 5) FRICTION
Rub the specimen vigorously on a soft cloth. True amber may omit a faint resinous fragrance but copal may actual begin to soften and the surface become sticky. Amber will also become heavily charged with static electricity and will easily pick up small pieces of loose paper.
(Test 6) TASTE
An antique trader who specialised in amber beads introduced this test to me. She explained that one of the most reliable tests she used was to taste the amber specimen after washing it in mild soapy water and then plain water. Whilst she could make no distinction between copal and amber, she could easily identify plastics and other common substitutes because of their unpleasant or chemical taste. Amber has hardly any taste at all. As a method for identification I have not seen this procedure recorded elsewhere. I can vouch for its effectiveness as a non-destructive method of differentiating between amber and certain other substances often misleadingly labelled amber.
(TEST 7) FLOTATION (Specific Gravity)
Mix 23gms of standard table salt with 200ml of luke warm water. Stir until completely dissolved. Amber should float in such a mixture and some copals together with various plastics sink.
(TEST 8) INCLUSIONS
Infrequently amber contains Flora or Fauna inclusions. Correctly identifying the trapped Insect or plant should be an excellent indicator of a piece’s authenticity. Most inclusions from ancient amber are of species that are now extinct or significantly changed. Frequently present in Baltic amber are tiny stellate hairs which are release by oak buds during their early growth and some time after,
(TEST 9) POLARISED LIGHT
Place the suspect piece of ‘amber’ between two sheets of polarising glass or plastic. (Kokin Filter Systems who sell lens accessories for cameras sell such products). Rotate one of the polarising lenses slowly through 360 degrees. In the body of the amber a display of rainbow colours should cycle through the transparent parts of the material. This is due to interference patterns being induced in the polarised light because of the internal strains and stresses within the amber itself. My general experience with this method is that genuine amber and copal always show these colour changes, where as some acrylics, polymers and certain plastic do not. Amber, which has been drilled and then later filled with a contemporary inclusion and resin also, reveals its self via the clear disruption of the colour display. Essentially; an amber piece which does not show interference patterns is unlikely to be true amber.
(TEST 10) KNIFE CUT
With a sharp knife try to shave off a tiny piece of the amber from an unobtrusive section. Real amber fractures and splinters. plastic and polymers actual cut and tiny shaved pieces can be removed without any splintering of the material.
In this article are a few pieces of genuine amber and non-genuine amber that you can find in our Arftire booths
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