igneous
Granite Pebble
Granite (Phaneritic intrusive rock)
Hardness: 6-7 Mohs; Color: Speckled brown, tan, and cream; Luster: Dull to vitreous; Crystal structure: Phaneritic (visible grains); Cleavage: Indistinct; Specific Gravity: 2.63-2.75
- Hardness
- 6-7 Mohs
- Color
- Speckled brown, tan, and cream
- Luster
- Dull to vitreous
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Physical properties
Hardness: 6-7 Mohs; Color: Speckled brown, tan, and cream; Luster: Dull to vitreous; Crystal structure: Phaneritic (visible grains); Cleavage: Indistinct; Specific Gravity: 2.63-2.75
Formation & geological history
Formed from the slow crystallization of magma below the Earth's surface. This specimen has been rounded by fluvial (water) or glacial erosion over thousands of years.
Uses & applications
Used in construction, decorative landscaping, and as an abrasive in polished form. Large deposits are used for dimension stone (countertops/monuments).
Geological facts
Granite makes up the majority of Earth's continental crust. It is primarily composed of quartz and feldspar, which give it its high durability.
Field identification & locations
Identifiable by its 'salt and pepper' speckled appearance and extreme hardness. Commonly found in river beds, beaches, and glacial till across all continents.
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