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Amethyst is a violet variety of quartz.The name comes from the Koine Greek αμέθυστος amethystos from α - a-, "not" and μεθύσκω (Ancient Greek) methysko / μεθώ metho (Modern Greek), "intoxicate", a reference to the belief that the stone protected its owner from drunkenness. [1]
An amethyst stone from South Africa. Amethyste or Amethystos (Ancient Greek: Ἀμέθυστη, romanized: Améthustē, lit. 'non-drunk') is supposedly a nymph in Greek mythology who was turned into a precious stone by the goddess Diana/Artemis in order to avoid a worse fate at the hands of the god Dionysus, thus explaining the origin of the semi-precious stone amethyst.
It is a mixture of amethyst and citrine with zones of purple and yellow or orange. Almost all commercially available ametrine is mined in Bolivia. The colour of the zones visible within ametrine are due to differing oxidation states of iron within the crystal. The citrine segments have oxidized iron while the amethyst segments are unoxidized.
Prasiolite (also known as green quartz, green amethyst or vermarine) is a green variety of quartz. Since 1950, almost all natural prasiolite has come from a small Brazilian mine, [ citation needed ] but it has also been mined in the Lower Silesia region of Poland .
Crystals of amethyst quartz Microscopically, a single crystal has atoms in a near-perfect periodic arrangement; a polycrystal is composed of many microscopic crystals (called "crystallites" or "grains"); and an amorphous solid (such as glass) has no periodic arrangement even microscopically.
In modern times gemstones are identified by gemologists, who describe gems and their characteristics using technical terminology specific to the field of gemology. The first characteristic a gemologist uses to identify a gemstone is its chemical composition. For example, diamonds are made of carbon (C) and rubies of aluminium oxide (Al 2 O 3).
The game has six different game modes: Survival, Challenging, Cruel, Harmless, Adventure, and Creative. The first four involve the player gathering necessary resources to stay alive. The Creative mode gives the player unlimited items and health, and the Adventure mode is used for quest and parkour maps.
An early use of the piezoelectricity of quartz crystals was in phonograph pickups. One of the most common piezoelectric uses of quartz today is as a crystal oscillator. The quartz oscillator or resonator was first developed by Walter Guyton Cady in 1921. [92] [93] George Washington Pierce designed and patented quartz crystal oscillators in 1923.