What do gemologists say about the green amethyst stone?

In my other posts I was discussing as much the physical properties of prasiolite as I considered the healing properties of green amethyst, or amethyst stone meaning. But in order to get a deeper insight into the origin of this stone, I thought I should go through some gemologist forums recently and try to find out what the experts think about this whole confusion about the name of green amethyst – nowadays very popular semi precious stone.

Gemology, just for the record, is a science that has evolved from mineralogy and it deals with gems, synthetic stones, imitations of stones and artificial gemstones. Many jewelry salespersons are educated gemologists. Apparently, they believe that virtually none of the green amethyst crystals that can be found on the market today are natural prasiolite, despite the fact that there are huge supplies of prasiolite specimens for sale. Furthermore, some of them think that the term "green amethyst" is more suitable than the term prasiolite. The reason is simple - one has to use amethyst and turn it into a green stone, which is not a natural prasiolite. If one insists on using the term prasiolite, then artificial prasiolite would be the right name. On the other hand, amethyst has always been associated with the purple color. Otherwise, citrine could be called brown or yellow amethyst, which is not the case, as we all know it so well. So, we have a really tricky situation here, and some of the experts think that this whole mess is just another marketing ploy aimed at robbing the unenlightened jewel clients.

So to summarize it altogether, we have all of these variations:

• Natural amethyst


• Irradiated amethyst


• Synthetic amethyst


• Natural citrine


• Heated citrine


• Synthetic citrine


• Natural ametrine


• Heated and/or irradiated ametrine


• Natural prasiolite


• Heated prasiolite


• Irradiated prasiolite


• Synthetic prasiolite

As you can see above, even more funny can be the situation with ametrine. Artificial ametrine can be produced by first heating amethyst to produce citrine and then irradiating citrine to partially change its color back into violet. This is really difficult to grasp, but that is how it is done.

Amethyst apparently gets its color from a so called "color center" defect inside the quartz matrix, and when heated to around 400 degrees C, this defect is removed and the result is a yellow citrine or greened amethyst. So, the term greened amethyst is more appropriate to describe the very process of creation - either artificial or natural; the crystal was purple at the beginning, and then it was turned into green color. Green amethyst on the other hand can indeed be synthesized as such, for example, in laboratory under proper conditions (e.g., addition of right admixture of bivalent iron, etc.).

This discussion above naturally summarize the answer to the question as to what the origin of prasiolite is or what color should green amethyst be. Often some people ask whether green amethyst comes in emerald green. I do not think you can get the emerald green color with prasiolite gemstones, but some specimens come really close to it. Bellow I will put some images to illustrate the difference in color among amethyst, citrine and ametrine. In the header image you may observe the color of green amethyst.

Amethyst












Citrine












Ametrine