![]() ![]() Type I gemstones with visible inclusions are rarely used for jewelry, unless set in a mounting that conceals the flaws. These stones are usually 'eye clean', meaning that no visible inclusions can be seen with the naked eye. Type 1 gemstones include beryl gems, such as aquamarine, heliodor (golden precious beryl) and morganite yellow and green chrysoberyl, pale color amethyst, citrine, smoky quartz, spodumene, tanzanite and blue zircon. ![]() Since colored gemstones vary so greatly, GIA (Gemological Institute of America) classifies colored gemstones as either 'Type 1', 'Type 2' or 'Type 3'. The colored gemstone clarity scale depends on the type of gemstone. Additionally, some inclusions are desirable, such as 'horsetail inclusions' in demantoid garnet and rutile 'silk' in sapphire. For example, the inclusions of emerald often provide evidence that it is natural. For colored gemstones, it is difficult to use a 'one size fits all' classification system for clarity, since some colored gemstones are expected to have inclusions and are sometimes even identified by their inclusions. This one is called “twilight fire.” .The gemstone clarity scale was created specifically for grading diamonds, more specifically, white diamonds - not colored gemstones. ![]() Irradiated: After white topaz is irradiated, it can acheive this color of electric “swiss blue.”Ĭoated: The eye catching “mystic topaz” is created using the coating treatment.Ĭoated: Many gemstone producers are experimenting with the coating treatment to create a wide range of “mystic” stones. Natural: This is what natural, untreated white topaz looks like If you rub a peice of quartz against a topaz, the quartz will scratch but the topaz will not. It can be distinguished from these by a scratch test, since topaz is harder than both of these materials. Topaz is imitated by quartz (citrine) and glass. Most jewelers will specify whether it is synthetic. In fact, synthetic topaz can be found at the same price if not more expensive than natural topaz. Synthetic topaz is not very prevalent on the market because natural topaz is so available. They are called “Mystic Topaz”, and new terms are coined every week. This process creates topaz that are a wide variety of irridescent, eye catching colors. Some topaz gemstones are treated with an extremely thin film of mineral or metalic materials and then placed in a vacuum. Only the surface layer of the gemstone is affected while the center remains colorless (you would not be able to tell unless you cut it in half). It involves coating the colorless topaz with a specific chemical and then heating it at very high temperatures. In recent decades, another method for improving the color of topaz was developed. In Europe this treatment is controversial and on its way to being banned because of the possible residual radioactivity of the gemstones. Sky Blue, London Blue and Swiss Blue are usually created using this treatment. Nearly all of the blue topaz on the market today has been irradiated in this way. Several decades ago, a technique was introduced of irradiating topaz colorless topaz to produce attractive shades of blue. For example, almost all pink topaz is created by heat treating yellow topaz. Topaz has been heat treated to improve color for decades, maybe even centuries. The listed treatments here are considered acceptable by the industry. Topaz seems to be becoming the gemstone with the widest variety of treatments imposed to affect its color. ![]()
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