Most gemstones, in the marketplace, have been treated in one form or another. Treatments are used to enhance color, improve clarity, or in some cases make a stone a whole new color. For example most Citrine, in the market today, is actually heat treated light purple Amethyst. Did you know that, I didnt until I started researching gemstones. Tanzanite, is heat treted to get the purple blue color, so desired. When it comes out of the ground it is brown, or green, 9 times out of 10. Treating of gemstones, is completely acceptable in the trade. It is however, illegal to not disclose to the consumer, that a stone has been treated. Treatments, make stones more beautiful, but they should also bring the value of the stone down some. So when purchasing gemstones, beware of the seller that will sell you a stone at extremely high prices, without revealing to you the stone has been treated. Here are some common forms of treatments, being used today.
1- Heat treatment, probably the most commonly used method of treating gemstones. It is used to enhance or change the color, of a gemstone.
2- Diffusion, a method similar to heat treating that intensifies the color of a gemstone.
3- Irradiation, a method used mostly for enhancing of color, or bringing on a totally new color. Alot of exotic colors of diamonds and topaz are irradiated. Blue diamonds, red diamonds, green diamonds, and very intense yellow diamonds are almost always irradiated.
4- Oiling and Waxing, is used to enhance gemstone color by filling in cracks and fissures. It does not appear this is a permanent treatment, and your stone may someday not be as lovely as when you purchased it.
5- Fracture filling coats gems with a clear or colored epoxy resin or another substance. The treatment fills-in cracks, which improves the appearance of the gemstone. This is very often done with rubies, and emeralds, where large amounts of inclusions are common. This is acceptable in the trade, however it does devalue your stone immensely so beware when purchasing stones. Be sure to ask if this treatment has been done, especially if you are paying a very high price per carat.
6- Laser drilling, removes inclusions thereby improving clarity. I have never heard of this one, and have no experience with it.
In conclusion, while most gemstones, in the market today are treated in someway, it should be disclosed to you. They are used to make stones more beautiful and lovely.