igneous

Granite Pebble

Granite (Phaneritic intrusive igneous rock comprising Quartz, Feldspar, and Mica)

Hardness: 6-7 on Mohs scale; Color: Mottled gray, white, and tan; Luster: Vitreous to dull; Crystal structure: Phaneritic (coarse-grained); Cleavage: None (fractures); Specific gravity: 2.63 - 2.75

Hardness: 6-7 on Mohs scale
Color: Mottled gray, white, and tan
Luster: Vitreous to dull

Identified March 26, 2026More igneous →

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Physical properties

Hardness: 6-7 on Mohs scale; Color: Mottled gray, white, and tan; Luster: Vitreous to dull; Crystal structure: Phaneritic (coarse-grained); Cleavage: None (fractures); Specific gravity: 2.63 - 2.75

Formation & geological history

Formed from the slow crystallization of magma below Earth's surface. This specimen appears to be a weathered fragment likely originating from the Precambrian or Paleozoic era and rounded by water or mechanical erosion.

Uses & applications

Used extensively in construction as aggregate, dimension stone for countertops and flooring, and in monument carving. Small pebbles are often used in landscaping and xeriscaping.

Geological facts

Granite makes up a large portion of the Earth's continental crust. It is extremely durable, which is why ancient Egyptian monuments like the obelisks and the Great Pyramid's interior chambers were constructed from it.

Field identification & locations

Identify by its 'salt and pepper' appearance and visible interlocking crystals. It is found globally in mountainous regions and cratons. Collectors look for unique mineral inclusions like garnet or tourmaline within the matrix.

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