Quartz is a mineral composed of silicon and oxygen atoms in a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO2. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar.
Quartz crystals are chiral, and exist in two forms, the normal α-quartz and the high-temperature β-quartz. The transformation from α-quartz to β-quartz takes place abruptly at 573 °C (846 K). Since the transformation is accompanied by a significant change in volume, it can easily induce fracturing of ceramics or rocks passing through this temperature limit.
There are many different varieties of quartz, several of which are semi-precious gemstones. Since antiquity, varieties of quartz have been the most commonly used minerals in the making of jewellery and hardstone carvings, especially in Eurasia.
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Very pretty. I would love to see it backlit to see how much of the light is able to penetrate.
ReplyDeleteThanks for linking up at https://image-in-ing.blogspot.com/2019/04/in-memoriam.html
Is that the natural shape in which quartz comes out of the ground? The crystals are beautiful.
ReplyDeleteYes, Hels. The crystals grow in hot supersaturated solutions that often develop in the cavities of hollow rounded rocks called geodes. Very large crystals develop and in some cases are so large that they may be carved into vessels, bowls, etc. Quartz is also called 'rock crystal'.
Deleteit is beautiful
ReplyDeleteMysterious gifts from our planet
ReplyDeleteHave a heartwarming en splendid ABC-Wednes-day / -week
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