igneous

Granite Pebble

Granite (Phaneritic Quartz-Feldspar intrusive rock)

Hardness: 6-7 Mohs; Color: Mottled gray, pink (potassium feldspar), and white; Luster: Dull to vitreous; Structure: Phaneritic (visible crystals); Cleavage: None (it fractures roughly).

Hardness: 6-7 Mohs
Color: Mottled gray, pink (potassium feldspar), and white
Luster: Dull to vitreous

Identified April 12, 2026More igneous →

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Physical properties

Hardness: 6-7 Mohs; Color: Mottled gray, pink (potassium feldspar), and white; Luster: Dull to vitreous; Structure: Phaneritic (visible crystals); Cleavage: None (it fractures roughly).

Formation & geological history

Formed from the slow crystallization of magma below Earth's surface. This specific specimen has been smoothed and rounded by water or glacial erosion, likely during the Quaternary period.

Uses & applications

In this small form, it is primarily a landscape or beach stone. In larger quantities, granite is used for construction, countertops, monuments, and as crushed stone for road base.

Geological facts

Granite is the most common rock found in the Earth's continental crust. The pink hue in this specimen suggests a presence of K-feldspar (orthoclase).

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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