sedimentary

Jasper (Red/Brown Variety)

Jasper (Microcrystalline Quartz, SiO2)

Hardness: 6.5–7 on Mohs scale; Color: Reddish-brown with variegated patterns; Luster: Vitreous to waxy; Crystal structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific gravity: 2.58–2.91

Hardness: 6
Color: Reddish-brown with variegated patterns
Luster: Vitreous to waxy

Identified March 28, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the infiltration of silica-rich fluids into volcanic ash or fine-grained sediments, typically undergoing low-grade metamorphism or hydrothermal replacement over millions of years (often Proterozoic to Cenozoic eras).

Uses & applications

Used extensively in jewelry (cabochons), lapidary art, decorative ornaments, and as a metaphysical healing stone. Historically used for making tools and seals.

Geological facts

Jasper’s name is derived from the Greek word 'iaspis', meaning spotted stone. It is almost always opaque and contains up to 20% foreign materials which determine its unique color and pattern.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), opacity, and smooth, waxy feel when polished or tumbled. Commonly found in riverbeds, desert regions, and volcanic areas in the USA (Oregon, Idaho), India, and Brazil.

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