igneous
Granite River Pebble
Granite (composed primarily of Quartz, Feldspar, and Mica)
Hardness: 6-7 Mohs; Color: Mottled grey, white, pink, and black; Luster: Dull to vitreous; Structure: Phaneritic (medium to coarse-grained); Cleavage: Diverse depending on mineral grains; Specific Gravity: 2.6-2.7
- Hardness
- 6-7 Mohs
- Color
- Mottled grey, white, pink, and black
- Luster
- Dull to vitreous
Identified More igneous →
Explore Granite River Pebble in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-7 Mohs; Color: Mottled grey, white, pink, and black; Luster: Dull to vitreous; Structure: Phaneritic (medium to coarse-grained); Cleavage: Diverse depending on mineral grains; Specific Gravity: 2.6-2.7
Formation & geological history
Formed from the slow crystallization of cooling magma beneath the Earth's surface over millions of years. This specific specimen has been shaped by water erosion in a river or coastal environment.
Uses & applications
Larger granite deposits are used for construction, countertops, and monuments; river pebbles are used in landscaping, aquariums, and decorative paving.
Geological facts
Granite is the most common rock found in the Earth's continental crust. Its name comes from the Latin word 'granum', meaning a grain, referring to its coarse-grained texture.
Field identification & locations
Identified by its visible interlocking grains of different colors. Commonly found in riverbeds, glacial deposits, and mountain ranges. Collectors look for unique mineral inclusions or banding.
