Amber – A Precious Gemstone

Amber is fossilized tree resin, which is produced by some trees as a form of protection from disease and wood-burrowing insects. It was one of the earliest gems used for personal adornment. Of special interest to scientists are ambers containing insects, pollen, leaves, and occasionally frogs and lizards that were trapped millions of years ago as the sticky resin dripped down the tree trunk.

Ambers with inclusions provide a rare look at the plant and insect life of that time period. Most amber is brownish yellow to orange in color but it can also be blue, green, or red. Brownish colors are the least valued. The best quality amber is transparent and either has no flaws or else has very distinctive inclusions.

The majority of gem-quality amber is found along the Baltic coasts of Russia and Poland. Other significant sources are the Dominican Republic, Mexico, Myanmar, Sicily, and Romania. Beware that Amber is sometimes dyed to make it darker or a different color. The dye may fade. Be on the lookout for pressed amber (also called reconstituted amber). It’s made by heating small amber fragments and compressing them into larger pieces. It can be identified by magnification.

A lot of natural ambers are heated just to make it more transparent. Amber can be separated from imitations such as plastic by placing it in a saturated salt solution. Amber will normally float while imitations may sink. However, copal and polystyrene plastic have about the same specific gravity as amber, so amber experts find high magnification to be more useful in detecting imitations. One imitation that is harder to detect is copal, a young version of amber.

It has essentially the same chemical formula as amber but different physical properties. Copal contains liquids such as oils, acids, and alcohol, whereas in amber these liquids have evaporated, resulting in a more durable product. Besides its greater resistance to cracking and crazing, amber is much more rare and valuable than copal. 

A drop of acetone nail polish remover on the back of the material can help separate copal from amber. The acetone will make copal sticky but it will have no effect on amber. Amber scratches abrade and melt easily. If it’s left in the sun, it can dehydrate and crack. Avoid ultrasonic’s, all chemicals, brushes, and heat. To clean amber, wipe it with a soft damp cloth; or clean it in cool soapy water, rinse and dry with a soft cloth.