igneous
Granite
Granite
Hardness: 6-7 on Mohs scale; Color: Pink, light gray, or white with dark specks; Luster: Vitreous to dull; Crystal structure: Phaneritic (coarse-grained); Cleavage: Perfect in certain mineral components like feldspar; Specific Gravity: 2.63 to 2.75.
- Hardness
- 6-7 on Mohs scale
- Color
- Pink, light gray, or white with dark specks
- Luster
- Vitreous to dull
Identified More igneous →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-7 on Mohs scale; Color: Pink, light gray, or white with dark specks; Luster: Vitreous to dull; Crystal structure: Phaneritic (coarse-grained); Cleavage: Perfect in certain mineral components like feldspar; Specific Gravity: 2.63 to 2.75.
Formation & geological history
Granite forms from the slow crystallization of magma below Earth's surface. It is composed mainly of quartz and feldspar with minor amounts of mica and amphiboles. It can range in age from the Precambrian to Cenozoic eras.
Uses & applications
Extensively used in construction for countertops, floor tiles, paving stone, curbing, and monuments. High-quality specimens are popular among amateur rock collectors.
Geological facts
Granite makes up a large portion of the Earth's continental crust. Mount Rushmore and the Egyptian pyramids contain significant amounts of granite or granite-related stones.
Field identification & locations
Identify by its interlocking granular texture where individual mineral grains are visible to the naked eye. Commonly found in mountainous regions or where ancient shields are exposed. Look for the distinct 'salt and pepper' appearance.
