Naturally occurring blue topaz is quite rare. Some imperial topaz stones can fade on exposure to sunlight for an extended period of time. Many brown or pale topazes are treated to make them bright yellow, gold, pink, or violet colored. Brazilian imperial topaz can often have a bright yellow to deep golden brown hue, sometimes even violet. Imperial topaz is yellow, pink (rare, if natural) or pink-orange. Blue topaz is the state gemstone of the US state of Texas. Orange topaz, also known as precious topaz, is the conventional birthstone for November, the symbol of friendship and the state gemstone of the U.S. In cut and polished form, it is used to make jewellery or other adornments.
In Europe during the Middle Ages, topaz was believed to enhance mental powers. It was also believed that wearing topaz increased body heat, which would enable people to relieve a cold or fever. During the Middle Ages, it was believed that attaching the topaz to the left arm protected the owner from any curse and warded off the evil eye. The ancient Romans believed that topaz provided protection from danger while traveling. Īn English superstition also held that topaz cured lunacy. However, because these translations as topaz all derive from the Septuagint translation topazi, which referred to a yellow stone that was not topaz, but probably chrysolite ( chrysoberyl or peridot), topaz is likely not meant here. Many English translations of the Bible, including the King James Version, mention topaz. 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. Nicols, the author of one of the first systematic treatises on minerals and gemstones, dedicated two chapters to the topic in 1652. Alternatively, the word topaz may be related to the Sanskrit word तपस् "tapas", meaning "heat" or "fire". Pliny said that Topazos is a legendary island in the Red Sea and the mineral "topaz" was first mined there. Ancient Sri Lanka ( Tamraparni) exported native oriental topazes to Greece and ancient Egypt, which led to the etymologically related names of the island by Alexander Polyhistor ( Topazius) and the early Egyptians ( Topapwene) – "land of the Topaz". The name topaz was first applied to the mineral now known by that name in 1737. 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. The name "topaz" is usually believed to be derived (via Old French: Topace and Latin: Topazus) from the Greek Τοπάζιος (Topázios) or Τοπάζιον (Topázion), from Τοπαζος. It is one of the hardest naturally occurring minerals and has a relatively low index of refraction. The rarest are natural pinks, reds, and delicate golden oranges, sometimes with pink hues. Topaz is often treated with heat or radiation to make it a deep blue, reddish-orange, pale green, pink, or purple.Īlthough it is often associated with golden yellow and blue, it comes in a variety of colors, including colorless. Common topaz in its natural state is colorless, though trace element impurities can make it pale blue or golden brown to yellow orange. It is used as a gemstone in jewelry and other adornments. Topaz is a silicate mineral of aluminium and fluorine with the chemical formula Al 2 Si O 4( F, OH) 2. Weak in thick sections X = yellow Y = yellow, violet, reddish Z = violet, bluish, yellow, pink
Colorless (if there are no impurities), white, blue, brown, orange, gray, yellow, yellowish brown, green, pink, reddish pink or even red
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