sedimentary

Jasper

Silicon dioxide (SiO2) with iron impurities

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs); Color: Reddish-brown, dark green, and yellow (mottled); Luster: Dull to waxy; Structure: Microcrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.91

Hardness: 6
Color: Reddish-brown, dark green, and yellow (mottled)
Luster: Dull to waxy

Identified March 16, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs); Color: Reddish-brown, dark green, and yellow (mottled); Luster: Dull to waxy; Structure: Microcrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.91

Formation & geological history

Formed through the deposition of silica from water-rich environments or within volcanic ash beds. Over millions of years, heat and pressure solidify the silica into microcrystalline quartz. Variations in mineral impurities (like iron oxides) create the specific coloring.

Uses & applications

Used primarily for semi-precious jewelry (beads and cabochons), ornamental vases, seals, and historical lapidary work. It is a popular stone for tumbling and rock collecting.

Geological facts

The name Jasper comes from the Greek word 'iaspis', meaning 'spotted stone'. It was considered a sacred protection stone in many ancient cultures, including the Egyptians and Native Americans.

Field identification & locations

Identify in the field by its opacity (even when held to light), smooth conchoidal fracture, and high hardness (cannot be scratched by a steel knife). Commonly found in riverbeds and mountainous regions across the United States, India, Brazil, and Russia.