igneous
Granite Cobble
Granite (composed primarily of Quartz, Feldspar, and Mica)
Hardness: 6-7 Mohs; Color: Pink, grey, and white phaneritic texture; Luster: Dull to vitreous; Structure: Massive, granular; Cleavage: None (fractures irregularly).
- Hardness
- 6-7 Mohs
- Color
- Pink, grey, and white phaneritic texture
- Luster
- Dull to vitreous
Identified More igneous →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-7 Mohs; Color: Pink, grey, and white phaneritic texture; Luster: Dull to vitreous; Structure: Massive, granular; Cleavage: None (fractures irregularly).
Formation & geological history
Formed from the slow crystallization of magma below the Earth's surface (plutonic). This specimen appears to have been rounded by water transport in a river or glacial environment.
Uses & applications
Used in construction, aggregate, landscaping, and as a common decorative garden stone.
Geological facts
Granite makes up a large portion of the Earth's continental crust. Its pink color is typically due to an abundance of potassium feldspar (orthoclase).
Field identification & locations
Identify by its 'salt and pepper' or multicrystalline appearance and its resistance to scratching. Commonly found in riverbeds, glacial tills, and mountain ranges.
