Pink Granite (Water-worn Cobble)

Physical Properties

Hardness: 6-7 (Mohs); Color: Mottled pink, grey, white, and black; Luster: Dull/earthy (weathered surface) to vitreous (fresh crystals); Structure: Phaneritic (coarse-grained) crystalline; Specific Gravity: 2.63 - 2.75

Formation & Geological History

Formed from the slow cooling of silica-rich magma deep within the Earth's crust (plutonic). This specific specimen has been Rounded by fluvial or glacial erosion. Granite can date from the Archean Eon to recent geological periods.

Uses & Applications

Commonly used in construction, countertops, monuments, and as decorative landscaping stones. Highly valued for its durability and resistance to weathering.

Geological Facts

Granite makes up the bulk of the Earth's continental crust. The pink color is specifically caused by an abundance of potassium feldspar (orthoclase). It is one of the hardest natural stones used by humans since antiquity.

Field Identification & Locations

Identify by its interlocking 'salt and pepper' texture with visible pink crystals. Often found in riverbeds, glacial tills, or mountain outcrops. It will not scratch with a copper penny but will scratch glass.

Identified on: 4/24/2026

Mode: Standard