igneous
Granite Pebble
Igneous Intrusive Rock (Quartz-Feldspar-Mica Phenocrysts)
Hardness: 6-7 Mohs; Color: Speckled white, grey, and black; Luster: Dull to vitreous; Structure: Phaneritic (crystalline); Specific Gravity: 2.63-2.75
- Hardness
- 6-7 Mohs
- Color
- Speckled white, grey, and black
- Luster
- Dull to vitreous
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Physical properties
Hardness: 6-7 Mohs; Color: Speckled white, grey, and black; Luster: Dull to vitreous; Structure: Phaneritic (crystalline); Specific Gravity: 2.63-2.75
Formation & geological history
Formed through the slow crystallization of magma below Earth's surface. Often Proterozoic or Paleozoic in age, typically found in continental crust environments.
Uses & applications
Used in construction (crushed stone), kitchen countertops, memorials, and as decorative river rock in landscaping.
Geological facts
Granite is the most common igneous rock found on Earth's continents and makes up the core of many mountain ranges like the Sierra Nevada.
Field identification & locations
Identify by its 'salt and pepper' appearance and visible interlocking crystals. Common in riverbeds and glacial tills. Very durable and resistant to weathering.
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