sedimentary

Granite Sand (Decomposed Granite)

Grus / Quartz-Feldspar Detritus

AI-generated identification · may be incorrect

Hardness: 6-7 (individual crystals); Color: Salt-and-pepper (tan, white, pink, black); Luster: Vitreous to dull; Structure: Granular/fragmented; Cleavage: Good in feldspar grains, absent in quartz.

Hardness: 6-7 (individual crystals)
Color: Salt-and-pepper (tan, white, pink, black)
Luster: Vitreous to dull

Identified February 22, 2026More sedimentary →

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Physical properties

Hardness: 6-7 (individual crystals); Color: Salt-and-pepper (tan, white, pink, black); Luster: Vitreous to dull; Structure: Granular/fragmented; Cleavage: Good in feldspar grains, absent in quartz.

Formation & geological history

Formed through the mechanical and chemical weathering (physical disintegration) of granitic igneous rock. This process often occurs over thousands of years in varied geological environments.

Uses & applications

Used extensively in landscaping, pathway construction, driveways, and as a stable base for pavers. Also utilized in horticulture for soil drainage.

Geological facts

This material is essentially the 'DNA' of the mountain it came from; it contains the exact mineral ratio of the parent granite. When it lithifies, it can eventually become a rock known as Arkose.

Field identification & locations

Identified by the mixture of translucent quartz grains, opaque white/pink feldspar, and dark flakes of biotite mica. Look for it at the base of granite outcrops or in dry riverbeds.