Amber, Baltic Sea area (various cut gems and utility objects). Photo © Joel E. Arem, PhD, FGA. Used with permission.
Venus figure of carved amber (pendant) from Eastern Europe, Neolithic period (around 10,200 to 4,500 BCE). Photo by Lisby. Public Domain.
Amber is a fairly common, easy-to-work gem material. A constant wonder to the eyes, it typically occurs in various shades of yellow, orange, and brown colors. On the other hand, pieces with green, blue, or violet tints due to extreme fluorescence are rare.
Amber also has a wide range of transparency. The transparent material is used almost exclusively for jewelry. Amber is often tumble polished and used for beads, pendants, earrings, and rings. Faceted pieces are rare.
The opaque material is frequently carved into artistic ornaments and inlays, as well as practical objects such as pipe stems and umbrella handles.
Amber is also burned as incense and used as an ingredient in perfumes.
Amber is an amorphous (non-crystalline) mixture of organic compounds, including hydrocarbons, resins, succinic acid, and oils. Most of this substance comes from the preserved resin of the pine species Pinus succinifera. However, other ancient tree species have also produced the material. Amber has been preserved for at least 30 million years.
What is Copal?
Preserved resin younger than 30 million years is known as copal, as is the organic gem material from the copal tree, Protium copal. Most gem pieces come from South America, Africa, and New Zealand. “Kauri Gum” is a copal from the kauri pine tree of New Zealand.
Often confused with each other, amber and copal have very similar properties with nearly identical origins. The principal difference is age.
Is Amber a Fossil?
Although amber is commonly referred to as fossilized resin, it’s not a fossil in the strictest sense. Most fossils begin when an animal or plant is buried in the earth. Over millennia, the organic material in fossils is slowly replaced with elements from the mineral kingdom. In contrast, amber’s organic elements haven’t been replaced. Instead, the resin has undergone a chemical transformation into a polymer, a natural plastic.
Amber is classed into various types. The sea type is found undersea. The pit variety is dug up from the ground, especially from the Baltic region. Other types are clear, massive, fancy, cloudy, frothy, fatty, and bone, in reference to their appearance.
Raw amber pieces from the Baltic region, left piece is 2.7 cm across, right piece is 3.1 cm across. Photo by James St. John. Licensed under CC By 2.0.
Amber is noted for its inclusions, which are chiefly insects, pollen, leaves, and other organic debris. Millions of years ago, still-living pine trees trapped these bits in their oozing, sticky fluids. These inclusions offer a remarkable view of life in those times. Some of the finer amber specimens contain whole, trapped termite colonies. The chambers of these structures, created with webbing, are still visible. Nursery chambers still contain egg sacks.
Besides termites and mosquitos, amber can contain many varieties of beetles, spiders, mites, and other arthropods. Sometimes, a single piece can contain many different kinds of organic inclusions.
Star spangles, flattened starburst shapes, are another type of inclusion. Caused by stress, these internal fractures radiate from a central point. While quite attractive, most are human induced. Hence, they don’t fetch the same value as a good-quality insect.
Amber Testing Techniques
Ancient techniques for identifying amber are still useful today. If rubbed vigorously on a piece of wool, the real deal will generate a static charge strong enough to pick up a small piece of ash. When it’s warm enough, it also gives off a distinctive, pleasant scent. These techniques may distinguish the genuine material from plastic imitations (and entertain inquisitive children).
A specific gravity (SG) test can also help weed out the plastic imitations. You can concoct a handy homemade testing liquid by boiling water and adding as much salt as you can dissolve in it. This will have a density of about 1.13. Amber, with a SG of 1.08, will float in this solution. Most plastics will sink. However, a few plastics have a density as low as 1.05. Many can have a lower SG than amber if they have air bubbles inside. So, if your sample sinks, you can be sure it’s not amber. If it floats, you still need to conduct more tests.
Only conduct destructive tests as a last resort to identify unfinished pieces.
Amber and plastic can share many visual characteristics. They can both have a refractive index (RI) of 1.540, so an RI reading is not definitive. Therefore, the next step is likely a hot point test.
This is a destructive test, but if conducted with care, it can leave no visible marks. First, find a place on your specimen where a mark would be as unobtrusive as possible (for example, on the bottom, an edge, or an area with existing scratches). Next, heat the tip of a needle until it glows red. Touch the selected spot just enough to release a tiny whiff of smoke. Now comes the hard part. Smell the smoke. If it’s genuine, it will smell like fine incense. If it’s plastic, it will smell chemical and offensive. (This is another reason to make your test on as small a scale as possible).
Distinguishing Amber from Copal
Although amber and copal share the same RI, SG, and most other properties, copal will fluoresce whiter in shortwave ultraviolet light than amber. (Making this judgement call depends on having tested enough samples of both materials to recognize the difference).
If you’re unable to make the distinction based on fluorescence, you’ll have to turn to a destructive test. On an inconspicuous area of the specimen, place a drop of acetone. Let it sit for three seconds, then wipe it off. Copal will have the surface damaged by the acetone, whereas amber will show little or no change from the brief exposure.
Pressed amber or ambroid is created by fusing smaller bits of amber under heat and great pressure. (Amber softens at about 150° C and melts at 250-300° C). A microscope examination can help distinguish amber from ambroid. In addition, amber often darkens with age to a fine red-brown color, while ambroid may turn white with age.
Plastic and glass pieces are sometimes used as simulants.
Amber can be darkened by heating. If done properly, this also creates star spangles. Dyeing is a common treatment.
Decorated with panels made from amber and backed with gold leaf, the celebrated Amber Room was originally constructed in the 18th century in the Catherine Palace near St. Petersburg, Russia. This “Eighth Wonder of The World” was looted during WWII and has disappeared. A reconstruction project was begun in 1979 and completed in 2003. This is the reconstructed chamber in the Catherine Palace. Photo by Dmitry Karyshev. Licensed under CC By 2.0
- The Baltic Sea Region, including Poland, Germany, and Russia: most of the world’s amber comes from a region formerly known as East Prussia and now known as the Kaliningrad Oblast, a Russian enclave.
- Sicily: material may be opalescent blue or green.
- United Kingdom: rarely found
- Norway; Denmark; Romania
- Myanmar: brownish yellow and brown varieties: also colorless, pale yellow, and orange.
- Lebanon: scarce, from very old deposits.
- Dominican Republic: mined from sedimentary rocks. Yellow, orange, and red colors. This material often contains well-preserved insects and sometimes displays a strong bluish tone in reflected light.
- Chiapas, Southern Mexico: produces golden yellow material.
- Cedar Lake, Manitoba, Canada.
- Point Barrow, Alaska.
Fragments normally weigh less than half a pound, but pieces weighing several pounds do turn up occasionally.
Avoid rough handling, heat, and chemicals. Solvents and alcohol can partially dissolve amber. Never use mechanical cleaning systems. Instead, use a damp cloth and warm-water detergent. Consult our jewelry cleaning guide for more recommendations.