Granite (weathered cobble)

Physical Properties

Hardness: 6-7 (Mohs scale); Color: Mottled cream, tan, and dark gray; Luster: Dull to vitreous; Crystal structure: Phaneritic (coarse-grained) with visible crystals of quartz, feldspar, and mica.

Formation & Geological History

Formed from the slow crystallization of magma below Earth's surface. This specific specimen is a rounded cobble, indicating it was weathered and transported by water, likely in a river or glacial environment.

Uses & Applications

Building material, countertops, paving stones, and memorial markers. In its raw form, it is crushed for road base construction.

Geological Facts

Granite is a major component of the continental crust. The white/cream parts are typically orthoclase or plagioclase feldspar, current gray/translucent parts are quartz, and dark flakes are likely biotite or hornblende.

Field Identification & Locations

Identified by its 'salt and pepper' appearance and visible interlocking crystals. It is extremely common in mountainous regions or areas with glacial deposits. Collectors value unusual colors or large crystal formations.

Identified on: 4/14/2026

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