Orange Quartzite (Tumble-polished)

Physical Properties

Hardness: 7 (Mohs scale); Color: Pale orange to honey-yellow; Luster: Vitreous to waxy; Crystal structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.6 - 2.8

Formation & Geological History

Formed from the metamorphism of quartz-rich sandstone. High heat and pressure cause the original quartz grains to recrystallize into a dense, interlocking mosaic of quartz crystals. Common in old mountain belts and shield regions.

Uses & Applications

Used frequently as decorative stones in landscaping, as tumbling rough for hobbyists, in jewelry (beads/cabochons), and industrially as a source of silica or for high-durability construction aggregate.

Geological Facts

Quartzite is so hard that it will scratch glass and even steel. It is often more durable than the parent sandstone and forms prominent ridges or weather-resistant outcrops in many mountain ranges.

Field Identification & Locations

Identify in the field by its grainy, 'sugary' texture and extreme hardness. Unlike calcite-based rocks, it will not fizz in contact with acid. Commonly found in areas with tectonic activity or ancient eroded mountain roots.

Identified on: 4/13/2026

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