There is much confusion about what green amber on the market really is and a question among amber experts as to how it should be labeled.
Retired paleobotanist and mineralogist Francis Hueber, formerly with the Smithsonian’s National Museum of Natural History, mentions that green amber is usually “that which reacts to exposure to ultraviolet light. The color is not a pigmentation but a physical reaction.” But most of the green amber does not have this property.
At jewelry and gift shows throughout the country today, you will often see brilliant green amber gems set in sterling silver. This may be Baltic amber, but it has been enhanced. As with most gems, there are enhancement techniques to enliven and brighten the stone. Where does the “green” come from?
In some cases it is obvious. Visual clues such as sun-spangle inclusions establish the material as “heated and pressure enhanced.” We are aware that amber can be clarified and shaped by using heat and pressure. Such amber is called “pressed,” and gem identification laboratories, such as the Gemological Institute of America’s Gem Lab, as well as suppliers of the material, are required by the Federal Trade Commission to label it “pressed amber.”
When it is green Baltic amber, remember, the natural green amber is rare in the Baltic countries and would not be so bright with inclusions and “sun spangles.” Currently, jewelers are applying a dark paste (almost like a paint) to the backs of the amber gems. The illusion of the dark paste through the honey-colored gem causes the beholder’s perception of green amber.
Amber is found in the Dominican Republic, “so it is certainly possible that it can be found on other Caribbean islands,” says Hueber. He also says that “the color [of this material], however, is quite unique.” He refers to a research paper discussing the lineage of the “amber tree,” including close, copal-producing relatives in West Africa, Mexico, the Caribbean Islands, Brazil, and Colombia.
Now the material called “copal” is not only similar to amber, but it is amber: young amber. Copal is a tree resin, but it’s less than 20 million years old and is softer than the old amber.
Maggie Campbell Pedersen, amber expert and author of Gem and Ornamental Materials of Organic Origin , published by Elsevier Butterworth-Heinemann (2004), notes that she has recently learned of “baked East African copal” that is supposed to “become amber.” Baked copal tends to have a greenish color. Pedersen says, “I have had some of this material tested, and it retains the infrared spectrum of copal.”
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