A group of topaz crystals on matrix
|Crystal class||Dipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m)
|Unit cell||a = 4.65 Å, b = 8.8 Å,
c = 8.4 Å; Z = 4
|Color||Colorless (if no impurities), blue, brown, orange, gray, yellow, green, pink and reddish pink|
|Crystal habit||Prismatic crystals with faces striated parallel to long dimension; also columnar, compact, massive|
|Fracture||Subconchoidal to uneven|
|Mohs scale hardness||8 (defining mineral)|
|Optical properties||Biaxial (+)|
|Refractive index||nα = 1.606–1.629
nβ = 1.609–1.631
nγ = 1.616–1.638
|Birefringence||δ = 0.010|
|Pleochroism||Weak in thick sections X = yellow; Y = yellow, violet, reddish; Z = violet, bluish, yellow, pink|
|Ultraviolet fluorescence||Short UV=golden yellow; Long UV=cream|
Topaz is a silicate mineral of aluminium and fluorine with the chemical formula Al2SiO4(F,OH)2. Topaz crystallizes in the orthorhombic system, and its crystals are mostly prismatic terminated by pyramidal and other faces.
Pure topaz is colorless and transparent but is usually tinted by impurities; typical topaz is wine red, yellow, pale gray, reddish-orange, or blue brown. It can also be white, pale green, blue, gold, pink (rare), reddish-yellow or opaque to transparent/translucent.
Orange topaz, also known as precious topaz, is the traditional November birthstone, the symbol of friendship, and the state gemstone of the US state of Utah.
Imperial topaz is yellow, pink (rare, if natural) or pink-orange. Brazilian Imperial Topaz can often have a bright yellow to deep golden brown hue, sometimes even violet. Many brown or pale topazes are treated to make them bright yellow, gold, pink or violet colored. Some imperial topaz stones can fade on exposure to sunlight for an extended period of time.
Blue topaz is the state gemstone of the US state of Texas. Naturally occurring blue topaz is quite rare. Typically, colorless, gray or pale yellow and blue material is heat treated and irradiated to produce a more desired darker blue.
Mystic topaz is colorless topaz which has been artificially coated giving it the desired rainbow effect.
Topaz is commonly associated with silicic igneous rocks of the granite and rhyolite type. It typically crystallizes in granitic pegmatites or in vapor cavities in rhyolite lava flows including those at Topaz Mountain in western Utah and Chivinar in South America. It can be found with fluorite and cassiterite in various areas including the Ural and Ilmen mountains of Russia, in Afghanistan, Sri Lanka, Czech Republic, Germany, Norway, Pakistan, Italy, Sweden, Japan, Brazil, Mexico; Flinders Island, Australia; Nigeria and the United States.
Brazil is one of the largest producers of topaz, some clear topaz crystals from Brazilian pegmatites can reach boulder size and weigh hundreds of pounds. Crystals of this size may be seen in museum collections. The Topaz of Aurangzeb, observed by Jean Baptiste Tavernier weighed 157.75 carats. The American Golden Topaz, a more recent gem, weighed a massive 22,892.5 carats. Large, vivid blue topaz specimens from the St. Anns mine in Zimbabwe were found in the late 1980s.
Colorless and light-blue varieties of topaz are found in Precambrian granite in Mason County, Texas within the Llano Uplift. There is no commercial mining of topaz in that area.
Topaz Mountain, Utah
Imperial Topaz from Ouro Preto, Minas Gerais, Brazil.
Colorless topaz, Minas Gerais, Brazil
Blue Topaz. St Anns Mine, Zimbabwe.
The name "topaz" is usually derived (via Old French: Topace and Latin: Topazus) from the Greek Τοπάζιος (Τοpáziοs) or Τοπάζιον (Τοpáziοn), from Τοπαζος, the ancient name of St. John's Island in the Red Sea which was difficult to find and from which a yellow stone (now believed to be chrysolite: yellowish olivine) was mined in ancient times; topaz itself (rather than topazios) was not really known before the classical era. Pliny said that Topazos is a legendary island in the Red Sea and the mineral "topaz" was first mined there. Alternatively, the word topaz may be related to the Sanskrit word तपस् "tapas", meaning "heat" or "fire".
Nicols, the author of one of the first systematic treatises on minerals and gemstones, dedicated two chapters to the topic in 1652. In the Middle Ages, the name topaz was used to refer to any yellow gemstone, but in modern times it denotes only the silicate described above.
Many modern English translations of the Bible, including the King James Version mention topaz. However, because these translations as topaz all derive from the Septuagint translation topazi[os], which as mentioned above referred to a yellow stone that was not topaz, but probably chrysolite (chrysoberyl or peridot), it should be borne in mind that topaz is likely not meant here. The masoretic text (the Hebrew on which most modern Protestant Bible translations of the Old Testament are based) has pitdah as the gem the stone is made from; some scholars think it is related to an Assyrian word meaning "flashed". More likely, "pitdah" is derived from Sanskrit words (पीत pit = yellow, दह् dah = burn), meaning "yellow burn" or, metaphorically, "fiery".
An English superstition held that topaz cured lunacy.
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العربية توباز ▪ Aragonés Topacio ▪ বাংলা পোখরাজ ▪ Беларуская Тапаз ▪ Беларуская (тарашкевіца) Тапаз ▪ Български Топаз ▪ Bosanski Topaz ▪ Català Topazi ▪ Čeština Topaz ▪ Dansk Topas ▪ Deutsch Topas ▪ Eesti Topaas ▪ Ελληνικά Τοπάζιο ▪ Español Topacio ▪ Esperanto Topazo ▪ Euskara Topazio ▪ فارسی زبرجد هندی ▪ Français Topaze (minéral) ▪ Gaeilge Tópás ▪ Galego Topacio ▪ 한국어 황옥 ▪ हिन्दी पुखराज ▪ Hrvatski Topaz ▪ Ido Topazo ▪ Bahasa Indonesia Topaz ▪ Italiano Topazio ▪ עברית טופז ▪ Basa Jawa Topaz ▪ ქართული ტოპაზი ▪ Kaszëbsczi Topaz ▪ Қазақша Топаз ▪ Latina Topazium ▪ Latviešu Topāzs ▪ Lietuvių Topazas ▪ Magyar Topáz ▪ മലയാളം ടോപാസ് ▪ مصرى توباز ▪ မြန်မာဘာသာ ဥဿဖယား ▪ Nederlands Topaas ▪ 日本語 トパーズ ▪ Norsk bokmål Topas ▪ Norsk nynorsk Topas ▪ Occitan Topazi ▪ Oʻzbekcha/ўзбекча Topaz ▪ پنجابی پکھراج ▪ پښتو توپاز ▪ Polski Topaz ▪ Português Topázio ▪ Română Topaz ▪ Runa Simi Q'illu umiña ▪ Русский Топаз ▪ Саха тыла Топааз ▪ සිංහල පඩියං ▪ Simple English Topaz ▪ Slovenčina Topás ▪ Slovenščina Topaz ▪ Српски / srpski Топаз ▪ Srpskohrvatski / српскохрватски Topaz ▪ Suomi Topaasi ▪ Svenska Topas ▪ தமிழ் புட்பராகம் ▪ తెలుగు పుష్యరాగం ▪ Türkçe Topaz ▪ Українська Топаз ▪ اردو پکھراج ▪ ئۇيغۇرچە / Uyghurche سېرىق قاشتېشى ▪ Tiếng Việt Topaz ▪ 中文 黄玉 ▪