Prasiolite

Common card · No. 348693

Prasiolite (also known as green amethyst or vermarine) is a green, transparent variety of quartz that derives its color from the presence of Fe2+ ions within the crystal structure. Prasiolite is not the only green variety of quartz, and it should not be confused with prase, chrysoprase, chrome chalcedony, or quartz colored by inclusions of chlorite or epidote. Natural prasiolite is exceedingly rare, having been first discovered in the early 19th century in Lower Silesia, Poland with only a few other deposits known to exist. Natural prasiolite deposits include Płóczki Górne (Poland), Bahia (Brazil), Thunder Bay (Canada), and Farm Rooisand (Namibia). Nearly all commercially available prasiolite is artificial, either produced by heat-treating amethysts from certain locations to 400-500 °C, or irradiating yellow-tinged quartzes. Most amethyst will turn yellow or orange when heated, producing heat-treated amethysts which are often marketed as citrine, but some amethyst will turn green when...

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