igneous
Granite Pebble
Granite (Felsic Plutonic Rock)
Hardness: 6-7 Mohs; Color: Tan, white, and grey speckled; Luster: Dull (weathered) to vitreous; Crystal structure: Phaneritic (medium-grained); Specific gravity: 2.63-2.75
- Hardness
- 6-7 Mohs
- Color
- Tan, white, and grey speckled
- Luster
- Dull (weathered) to vitreous
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Physical properties
Hardness: 6-7 Mohs; Color: Tan, white, and grey speckled; Luster: Dull (weathered) to vitreous; Crystal structure: Phaneritic (medium-grained); 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 and smoothed by water erosion in a river or coastal environment.
Uses & applications
Used widely in construction (crushed stone), kitchen countertops, memorials, and as decorative landscaping gravel.
Geological facts
Granite makes up a large portion of the Earth's continental crust. It is one of the hardest and most durable common substances on the planet.
Field identification & locations
Identify in the field by its 'salt and pepper' appearance and visible interlocking crystals of quartz and feldspar. Commonly found in riverbeds, glacial tills, and mountainous regions.
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