Red Quartzite

Physical Properties

Hardness: 7 (Mohs scale), Color: Reddish-brown to pink, Lustre: Vitreous to dull, Crystal Structure: Hexagonal (microcrystalline), Cleavage: None (conchoidal fracture), Specific Gravity: 2.6-2.7

Formation & Geological History

Formed from regional metamorphism of quartz sandstone. The intense heat and pressure cause the sand grains to recrystallize and fuse together. The red color suggests the presence of hematite or other iron oxides during formation.

Uses & Applications

Used in construction as crushed stone for road beds, railway ballast, and as a decorative stone in landscaping. Its hardness makes it ideal for abrasive applications.

Geological Facts

Quartzite is so tough that when it breaks, the fracture passes right through the quartz grains rather than along their boundaries, unlike the sandstone it originated from.

Field Identification & Locations

Identify by its extreme hardness (cannot be scratched by a steel blade) and its grainy, crystalline texture that lacks the distinct layering of some other metamorphic rocks. Often found in mountain belts and ancient shield areas.

Identified on: 4/17/2026

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