![]() ![]() Topaz occurs in a wide range of natural colors however, most natural topaz is colorless. ![]() But, as the topaz crystal expanded, it pushed the tiny crystal in the direction of growth, and a wispy stream of inclusions within the topaz was the result. The tiny crystal made it difficult for the topaz below it to grow properly - it had become an obstacle to growth. Instead it is a tiny crystal of an unidentified mineral that started to grow on the surface of a much larger topaz crystal. These colors are very rare.Ĭomet Tail Inclusion in Topaz: It looks like a comet flying through a gemstone. The most valuable colors for use in jewelry are natural pink, orange, red, purple and blue. Diamond, corundum, and chrysoberyl are the only commonly known minerals that are harder than topaz. Every student who takes a physical geology course learns about the exceptional hardness of topaz. It has a hardness of 8 on the Mohs hardness scale, making it the hardest silicate mineral. One of the best-known physical properties of topaz is its hardness. Hardness, prismatic crystals, sometimes striated, cleavage, specific gravity. Occurs in a wide range of treated colors, most often blue.Ĭolorless - harder than the streak plate. Natural colors include: colorless, yellow, orange, brown, red, pink, blue, green. Today, over 200 years later, his hardness scale is still used by students and geologists throughout the world to identify mineral specimens. In 1812, Friedrich Mohs developed a set of 10 standard minerals that could be used to assign a relative hardness to minerals and other materials. The most affordable and frequently purchased are blue topaz and mystic topaz that have received their colors from treatment. Natural topaz colors include rare and valuable yellow, orange, pink, red, purple, and blue. Topaz obtains much of its popularity from its beautiful colors and its status as a birthstone. It is best known for being these four things: Topaz is a rare silicate mineral with a chemical composition of Al 2SiO 4(F,OH) 2. Specimens and photos by Lockwood and Sloan. The rarity and value of these natural topaz colors is lowest at the bottom of the photo and highest at the top. At the top are orangy pink and purplish pink gems that are sometimes called "pink topaz". Some gemologists would call these two specimens "imperial topaz" because they display reddish orange pleochroic colors on both ends of the gem. ![]() Starting at the bottom is yellow topaz, sometimes called "golden topaz". Natural Topaz Colors: A collection of faceted topaz in a variety of colors. ![]()
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