igneous
Granite
Felsic Plutonic Rock (Granite)
Hardness: 6-7 (Mohs scale); Color: Pink/brown (orthoclase), white/grey (quartz), black (biotite/hornblende); Luster: Vitreous; Crystal Structure: Phaneritic (coarsegrained/plutonic).
- Hardness
- 6-7 (Mohs scale)
- Luster
- Vitreous
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Physical properties
Hardness: 6-7 (Mohs scale); Color: Pink/brown (orthoclase), white/grey (quartz), black (biotite/hornblende); Luster: Vitreous; Crystal Structure: Phaneritic (coarsegrained/plutonic).
Formation & geological history
Formed through the slow crystallization of magma below the Earth's surface (intrusive). Most granite dates to the Precambrian or Paleozoic eras and forms in the cores of mountain ranges.
Uses & applications
Extensively used in construction for countertops, floor tiles, paving stone, monuments, and as crushed stone for road base.
Geological facts
Granite makes up a large portion of the continental crust. The word comes from the Latin 'granum', meaning a grain, in reference to its coarse-grained structure.
Field identification & locations
Identify in the field by its interlocking 'salt and pepper' appearance and visible crystals. It is found globally in continental shields and mountain belts like the Rockies or Appalachians.
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