Putting the finishing touches on a stunning cluster pearl necklace, I saw that the clear green crystalline stones accenting my pearly creation had entered my design as an unknown entity.
Not a clue from my Tucson Gem Show receipts revealed what they were. I would need to make the determination by investigation and analysis, otherwise known as gemstone sleuthing.
It’s not like me not to know the identity of gemstones in my jewelry supplies. No label accompanied the strand of pretty accent stones. I knew about them only what I could see. What I observed was a very pale green color, crystalline and clear.
A search of my mental database yielded prehnite as the pale green stone. The color was right, but the opacity was wrong. Prehnite is opaque. My crystals were water clear.
Next in the gemological investigation was an online search for clear crystals with the pale green color. Online photos of zultanite gemstones looked remarkably like my unidentified crystals. As a diaspore, zultanite changes color with changing lighting conditions. What appears as a crystal of pale green in daylight changes to gentle champagne under incandescent lighting. Some zultanite crystals show as a pale rose color when incandescent lighting is turned down low.
If my crystals were zultanite, I could expect to see their color change from the pale green they were in bright daylight. Neither incandescent lighting nor low light conditions produced a change of color in my crystals. Back to the drawing board!
The final possibility of prasiolite for my crystals proved fruitful. Prasiolite is the green form of amethyst, which is better known as a purple crystal rather than a green one. But when amethyst is heat treated and irradiated with cobalt-60, it turns from purple to pale green. The color change created in this way is permanent and does not depart from the pale green color the amethyst has become.
- Because my crystals were clear, they were not prehnite.
- Because my crystals did not change color with change in lighting, my crystals were not zultanite.
- Because my crystals matched the known gemstones in earrings made of green amethyst, I concluded that they are green amethyst, which is the other name for prasiolite.
It was then that I recalled my conversation with the vendor from India from whom I purchased the crystals. I asked him what they were. He pronounced an unintelligible gemstone name that seemed to start with a “P.” Unfamiliar with the name at the time, I asked him to clarify, to which he replied, “prasiolite, same as green amethyst.” Mystery solved!
It’s all coming back, as clear as a pale green crystal called prasiolite!