Since the screening of 'Jurassic Park' interest in the mineral amber has grown significantly. Unfortunately so has 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 bee 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 bee 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.

In some cases copal, which is tree resin which has not yet fully fossilized 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.

There are a number of simple tests which can be carried out on amber to check its authenticity. I have listed here all the basic methods I have come across. 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.

HARDNESS

Amber has a hardness on Mohs scale in the region of 2 - 3. Using appropriate scratch sticks it should be reasonably straightforward to test the sample under question.

HOT NEEDLE

Heat a needle point 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 emits a light fragrant odor. Amber when tested does not melt as quickly as the copal and emits sooty fumes.

SOLUBILITY

Copal will dissolve in acetone. This test can be done by dispensing the acetone from an eye dropper 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.

UV LIGHT

Copal under a short-wave UV light shows hardly any color change. Amber fluoresces a pale shade of blue.

FRICTION

Rub the specimen vigorously on a soft cloth. True amber may emit 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.

TASTE

This test was introduced to me by a antique trader who specialized in amber beads. 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 labeled amber.

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.

INCLUSIONS

Infrequently amber contains Flora or Fauna inclusions. Correctly identifying the trapped Insect or plant should be an excellent indicator of a pieces authenticity. Most inclusions from ancient amber are of species which are now extinct or significantly changed.

POLARIZED LIGHT

Place the suspect piece of amber between two sheets of polarizing glass or plastic. (Kokin Filter Systems which sell lens accessories for cameras sell such products). Rotate one of the polarizing lenses slowly through 360 degrees. In the body of the amber a display of rainbow colors should cycle through the transparent parts of the material. This is due to interference patterns being induced in the polarized 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 color 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 color display. Essentially; an amber piece which does not show interference patterns is unlikely to be true amber.

Anyone wishing to find out more about amber in general or these test methods specifically would do well to consult one of three books currently available on amber, they are:

Life In Amber; George O. Poinar, Jr.; Stanford University Press; ISBN: 0-8047-2001-0.
Amber - The Golden Gem of the Ages; Patty C. Rice; The Kosciuszko Foundation, Inc.; ISBN: 0-917-00720-5.
Amber - Window to the Past; David Grimaldi; Harry N Abrams; ISBN: 0-8109-1966-4.

Now back to the bee I mentioned earlier. I am afraid that only the eighth and ninth tests would have identified this particular fake. The item consisted of a block of true amber into which had been drilled a hole large enough to receive the dead bee. Resin which had been melted was then poured back over the insect, encasing it in an apparently genuine amber prison.

Mineralogical Meanderings

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Bob Keller