igneous
Granite
Granite (dominated by Quartz, Alkali Feldspar, and Plagioclase)
Hardness: 6-7 on Mohs scale; Color: Mottled white, pink, and grey; Luster: Dull to vitreous; Crystal Structure: Phaneritic (coarse-grained); Cleavage: Indistinct; Specific Gravity: 2.63 to 2.75
- Hardness
- 6-7 on Mohs scale
- Color
- Mottled white, pink, and grey
- Luster
- Dull to vitreous
Identified More igneous →
Explore Granite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-7 on Mohs scale; Color: Mottled white, pink, and grey; Luster: Dull to vitreous; Crystal Structure: Phaneritic (coarse-grained); Cleavage: Indistinct; Specific Gravity: 2.63 to 2.75
Formation & geological history
Formed through the slow crystallization of magma below Earth's surface (intrusive). It is found in continental crust and can date from several billion to a few million years old.
Uses & applications
Extensively used in construction for countertops, floor tiles, paving stone, curbing, and monuments. Also a popular specimen for educational rock collections.
Geological facts
Granite is the most common igneous rock found on Earth's continents and makes up the core of many mountain ranges. The pink color in this specimen is likely due to the presence of potassium feldspar (orthoclase).
Field identification & locations
Identify by its 'salt and pepper' appearance and visible interlocking crystals. Common in mountain regions and glacial till. Collectors should look for unique mineral inclusions like garnet or tourmaline.
