sedimentary

Jasper

Microcrystalline Quartz (Chalcedony), SiO2

Hardness: 6.5 to 7 on the Mohs scale; Color: Brown, red, yellow, green, or multicolored; Luster: Vitreous to dull; Crystal Structure: Trigonal (microcrystalline); Cleavage: None, exhibits conchoidal fracture; Specific Gravity: 2.58 to 2.91

Hardness: 6
Color: Brown, red, yellow, green, or multicolored
Luster: Vitreous to dull

Identified August 7, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the silification of sedimentary or volcanic rocks where silica-rich fluids replace original material, often in hydrothermal environments or marine sediment deposits over millions of years.

Uses & applications

Used in ornamental carvings, cabochons for jewelry, decorative objects, and as a popular specimen for rock collectors.

Geological facts

Jasper has been used throughout human history since ancient times for talismans, seals, and primitive tools due to its toughness and ability to take a fine polish.

Field identification & locations

Can be identified in the field by its hardness (scratches glass), waxy to dull luster, opaque appearance, and conchoidal fracture. Commonly found in riverbeds, ancient marine deposits, and mountainous regions worldwide.

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