QUARZ
HARDNESS: 7
DENSITY: 2,65 g/cm3
SCRATCH: White
COLOR: Colorless to very varied coloration
BRIGHTNESS: Vitreous, silky, matte
EXFOLIATION- FRACTURE: None - Concoidea
CRYSTALLIZATION: Trigonal system
TRANSPARENCY: Transparent to translucent, opaque
Quartz is a mineral composed of silicon dioxide. It has so much hardness that it can scratch common steels. His tenacity is fragile. It is the most abundant mineral in the earth's crust. It presents colored varieties such as amethyst, smoky quartz, citrine, onyx, sardonyx and heliotrope, etc. Dipiramidal crystals to tabular, acicular, prismatic long to short, fibrous aggregates, botryoidal and stalactitic and layers, concretions, geodes, granular masses and compact masses.