The value of a "living" gemstone is directly related to its rarity. Most of us have heard of using the 4 "C" s color, clarity, cut and carat, when determining the value of a gemstone. Weighing very on the rarity of a gemstone is color, clarity and cut, having to do with the quality of the stone and carat having to do with the size. Larger stones or stones with good color or clarity have a greater value because they are rarer. Keep in mind that color, probably being of most importance in colored gemstones, is of no importance when speaking of the brilliancy of a diamond where clarity and cut are used in determining its value. That being said, there is one more important piece of information to which many may be unaware and that is whether or not your stone has been treated or as some dealers describe it, enhanced.
Did you know that the treatment or enhancement of your gemstone can directly affect its value? For example, a large, untreated, (color unchanged) stone is much more desirable on the marketplace than a similar "tated" stone and will never lose its color or beauty. A natural, untreated ruby or sapphire, for instance, can have up to 400% more market value than a similar heated ruby or sapphire. It is, therefore, undeniably important to totally understand gem treatments or improvements at every level. Below are various methods of gemstone treatments along with information on how to detect that a gemstone has been treated, along with the disadvantages of certain treatments.
Living gemstones are routinely heated under controlled conditions to improve color, alter color, or improve clarity. Since natural heating also occurs under natural conditions, the artificial effects are sometimes indistinguishable from natural effects. Gemstones are normally heated at temperatures of 1200 degrees C, but can go as high as 1,800 ° C. Why does this matter? Your "magic" gemstone can become more brittle, causing fractures and chips. Be leery of dealers who claim that their gemstones were only treated using lower heats. That is sort of comparable to one becoming "a little bit pregnant". High quality unheated rubies and sapphires are extremely rare and command a much higher market price than the heated, but, understand that unheated / untreated specimens are almost non-existent. As a result, always purchase from a reliable supplier or have the seller's claim that a gemstone is untreated verified by a gemologist.
Radiation treatment is done to change the color of the gem, particularly in colored diamonds and topaz. Some diamonds may show microscopic characteristics indicative of radiation, such as a scalloped pattern around the culet or brownish radiation "spots" on the surface, but one normally needs high tech equipment in determining this type of treatment in a gemstone. R. Webster's Gems, fifth edition says that, '' A recent examination of a green diamond treated with americium-241 oxide indicated that this stone was not only radioactive, but that it could not be safely worn until the year 5071. "Hoping that This would be the exception rather than the rule, it would still be prudent to buy from a reputable dealer, especially if you are purchasing topaz or colored diamonds. Further insist on a report from a certified gemologist when making any substantive gemstone purchase.
Beryllium treatment is a bulk diffusion process which which commonly uses beryllium, but may also include other chemicals such as lithium and titanium. Beryllium is not only a highly toxic substance, but all the beryllium salts are known to be carcinogenic. As a result of this, the release of any beryllium or vaporized salts during the high temperature treatment process could have significant health consequences. There was even some concern that the there may be very small temporary amounts left on the gemstone. Be aware that, many heated rubies and sapphires that were actually beryllium treated were only detected as heat treated by most of the world's labs. Unfortunately most labs do not have the very expensive equipment needed to detect a Beryllium treated living gemstone.
Fracture Filling is the process of filling surface breaking fractures with additives to improve clarity and or color. Emeralds commonly have their surface reaching cracks filled with resins, oleo-resins however with or without hardeners the treatment may not be stable. Beware of unscrupulous dealers who can add flux or glass in order to add extra weight to the gemstone, can use this treatment to get higher prices for their gemstones. Certainly, if you are aware of what you are buying, this process can provide some nice looking stones for a lot less money.
Laser drilling is the process that is commonly used in diamonds. A laser is used to bore a small hole in the diamond and burn an inclusion from the inside out. By reaching a dark inclusion with acid, the inclusion is bleached to a lighter color. Laser drilling makes the condition of the stone much less visible since it causes the inclusions to become invisible. It is extremely important that the laser drilled diamond be priced according to its original clarity grade and not the new clarity grade after treatment. Diffusion is a treatment used to deepen a gemstone's color by baking a layer of color into the gemstone's surface. This produces a false color for the stone and this treatment only intensifies a gemstone's outer layers. The problem with this treatment is that the color can ever scratch off. Diffusion can be easily detected by a gemologist using a 10X magnification loupe. (Reference: http://yourgemologist.com )
So remember, treatments and improvements are not always a bad thing. Some treatments produce beautiful stones and you can get more "bang for your buck" when purchasing a treated gemstone. But treatments can go either way since they create permanent changes in some gems and temporary changes in others. Therefore, the only way to be sure that your beautiful "magic" gemstone will stay beautiful forever is to buy them natural and untreated. And remember, before purchasing a living gemstone, be sure to buy from a reputable dealer, get a gemologist's report and familiarize yourself with the information and terminology provided above.
Source by Patricia Kraus