Amber Buying and the Four Cs
The IGS amber value listing has price guidelines for cabochons with or without insects as well as rarely encountered faceted pieces.
Color
Most amber is yellow to orange or brown. Deep yellow colors command higher prices.
Natural cherry-red pieces are very rare and sell at a premium. However, most red amber undergoes heat treatment to achieve this color.
Green Amber
While heat treatments can produce deep green hues, some yellow-green amber occurs naturally. Since this material contains large amounts of soil and other organics, its sobriquet of “earth amber” is certainly fitting.
Blue Amber
With a unique surface fluorescence, blue amber makes a delightful gem. Arising from only one extinct tree species, this rare amber appears blue on the surface but glows yellow to red within.
Clarity
Due to its origins as tree sap, amber often contains bubbles that reduce the material’s clarity. As a result, highly transparent material is rare and most valuable. It’s typically cabbed for jewelry. Opaque amber, on the other hand, is generally carved or even burned as incense.
Amber may contain soils, plants, and animals as inclusions. Plants preserved in amber, while valuable to scientists, have…