QUARTZ (Cuarzo)
Classification: SILICATE
PHYSICAL PROPERTIES
COLOUR: Colourless, purple, white, pink, brown and black. Also gray, green, orange, yellow, blue and red
STREAK: White
LUSTRE: Vitreous
CLEAVAGE: None
HARDNESS: 7
CHEMICAL FORMULA: SiO2
Main Uses
Quartz is one of the most useful natural materials. Its usefulness can be linked to its physical and chemical properties. It has a hardness of seven on the Mohs Scale which makes it very durable. It is chemically inert in contact with most substances. It has electrical properties and heat resistance that make it valuable in electronic products. Its luster, color, and diaphaneity make it useful as a gemstone and also in the making of glass.
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