sedimentary

Coarse-grained Jasper or Jasper Conglomerate

Silicon Dioxide with Iron Oxide (SiO2) + Fe2O3

Hardness: 6.5-7 (Mohs scale), Color: Rusty red, orange, and tan/grey, Luster: Dull to waxy, Crystal Structure: Microcrystalline quartz, Cleavage: None (conchoidal fracture), Specific Gravity: 2.6-2.9.

Hardness: 6

Identified March 26, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed via the deposition of silica-rich fluids through porous rock or soil, often in volcanic or sedimentary environments. The red coloration is due to the oxidation of iron (rusting) during the mineralization process. These can range from modern geological ages to millions of years old.

Uses & applications

Used primarily for lapidary work (cabochons and beads) and as decorative landscaping stone. In industry, high-silica stones are used as abrasives.

Geological facts

Jasper is often referred to as the 'Supreme Nurturer' in metaphysical circles. In geological terms, the red color is almost always a result of iron impurities that have hematite inclusions.

Field identification & locations

Identify by its hardness (it will scratch glass and a steel knife blade) and the appearance of small, rounded clasts or grains cemented by a red matrix. This is common in iron-rich areas like the Great Lakes region or the American West. Collectors should look for unique banding or patterns.

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