Orange Quartzite (with Iron Staining)

Physical Properties

Hardness: 7 (Mohs scale); Color: Orange, peach, and white; Luster: Vitreous to dull; Crystal structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific gravity: 2.63 - 2.65.

Formation & Geological History

Formed through the metamorphism of quartz-rich sandstone. High heat and pressure causes recrystallization of the quartz grains into a dense, hard rock. The orange color is typically caused by iron oxide (limonite or hematite) infiltration during or after formation.

Uses & Applications

Used primarily as decorative stone, construction aggregate, and occasionally in lapidary work for tumbling or carving.

Geological Facts

Quartzite is often harder and more durable than the granite it may resemble. It is so tough that it often breaks through the constituent quartz grains rather than around them.

Field Identification & Locations

Identify in the field by its inability to be scratched by steel and its granular, sugary texture. Common in ancient mountain belts and riverbeds as water-worn pebbles.

Identified on: 4/17/2026

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