Color of Topaz loose sale price & Topaz Gemstone Information
Brown, yellow, orange, sherry, red and pink topaz is found in Brazil and Sri Lanka. Pink topaz is found in Pakistan and Russia. Today we also have blue topaz, which has a pale to medium blue color created by irradiation. Pale topaz which is enhanced to become blue is found in Brazil, Sri Lanka, Nigeria, and China. In early 1998, a new type of enhanced topaz made itsappearance, the surface-enhanced topaz, with colours described as blue to greenish-blue or emerald green. Blue topaz has become a popular alternative in recent years for those who prefer faceted stones. Topaz occurs in a range of magnificent colors -- blue, pale green, varying shades of yellow, pink, red, brown and even black. Pure topaz itself is a colorless stone. Red and some pink topaz get their colors from chromium that is substituted for aluminum in the crystals. But most other colors occur due to minor element substitutions and defects in the crystal. Some colors are unstable and can fade away; for example, brown topaz mined in Siberia can be bleached by sunlight. In other stones, color changes can be induced by heating. High energy irradiation and moderate heat treatment of colorless topaz can transform it to blue gemstones. Topaz commonly occurs in colorless and brown colors, it is the rare golden, orange, pink, red and purple colors, which are often termed “precious” or “imperial” topaz, that are the mainstay of the fine gem market. While blue topaz is found in nature, most of the material is produced by a combination irradiation/heating treatment. Yellow and brown topaz owe their color to color centers. The impurity chromium produces pink to red colors. A combination of color centers and chromium produces orange topaz. Blue topaz is colored by color centers. Note that the color of some brown topaz may fade with time.
SwissGemShop - Loose Precious & Semi Precious Gemstones - Gemstone at sale price in Jewelry quality. A lot of Gem information, learn about Gemstones !
Swiss Gem Shop loose Gemstone at Sale price and Gemstone Information