Kyanite

Kyanite is an alumino-silicate mineral often found in metamorphic rocks, such as pegmatites.  It forms thin blade-like crystals that often radiate from a common centre.  The name kyanite comes from the Greek kuanos or kyanos, meaning ‘deep blue’, however not all kyanites are blue!  Kyanite can be black, green, orange, with the white/grey variety called rhaeticite.

File:Kyanite crystals.jpg

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Jade

Jade is a beautiful green ornamental stone that has been used for centuries in many parts of the world.  However gemstone jade can actually come from two metamorphic sources, both similar in texture, hardness, and appearance.  Nephrite is a form of Actinolite (an amphibole-silicate mineral whose fibrous form is known as Asbestos), and the other source is Jadeite, a pyroxene.

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