igneous
Granite
Granite (composed primarily of silica-rich minerals like quartz and feldspar)
Hardness: 6-7 on Mohs scale; Color: mottled grey, pink, and white; Luster: dull to vitreous; Crystal structure: phaneritic (coarse-grained); Specific gravity: 2.63 to 2.75
- Hardness
- 6-7 on Mohs scale
- Color
- mottled grey, pink, and white
- Luster
- dull to vitreous
Identified More igneous →
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Physical properties
Hardness: 6-7 on Mohs scale; Color: mottled grey, pink, and white; Luster: dull to vitreous; Crystal structure: phaneritic (coarse-grained); Specific gravity: 2.63 to 2.75
Formation & geological history
Formed by the slow crystallization of magma below Earth's surface. This specimen appears water-worn, likely from a fluvial (river) or coastal environment. Common in continental crust formations.
Uses & applications
Extensively used in construction for countertops, floor tiles, paving stone, curbing, and monumental architecture. Also valued as a collector's specimen when containing unique mineral inclusions.
Geological facts
Granite is one of the oldest and most abundant rocks on Earth. It makes up much of the continental crust and the hearts of many mountain ranges.
Field identification & locations
Identified by its visible interlocking crystals of different colors (quartz, feldspar, and mica). Found worldwide in crystalline basement rocks and glacial till. This specimen shows significant rounding due to water erosion.
