Granite
Image: <a href="//commons.wikimedia.org/wiki/User:W.carter" title="User:W.carter">W.carter</a> (CC0)
Mineral NameGranite
Chemical FormulaGranite is a rock composed primarily of quartz (SiO2), feldspar (KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8 series), and mica (e.g., KAl2(AlSi3O10)(OH)2). It does not have a single chemical formula.
Mohs Hardness6
Streak ColorWhite to colorless
CleavagePoor to none (for the rock as a whole, but constituent feldspar has good cleavage)
FractureUneven to conchoidal (for quartz component)
Specific Gravity2.65
Colorsreddish-brown, orange, pink, white, gray, black
Transparencyopaque
Type LocalityLoddebo, Lysekil Municipality, Sweden
Mineral GroupIgneous Rock (Plutonic)
Usesbuilding material, countertops, flooring, monuments, construction aggregate
Associated Mineralsquartz, feldspar, biotite, muscovite, amphibole
Raritycommon
Description
The image displays a large, weathered granite cliff face, predominantly reddish-brown and orange in color, showing evidence of exfoliation and lighter streaks from reflecting feldspar crystals. The rock surface appears smooth in places due to weathering, with some darker patches and remnants of a handrail at the top.
Geological Context
Granite is a felsic intrusive igneous rock that forms from the slow crystallization of magma deep beneath the Earth's surface. It is a major component of continental crust, often exposed in mountain ranges and cratonic shields after uplift and erosion.
