mineral

Tumbled jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), commonly containing iron oxides and other silicates

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; opaque, reddish-brown, olive, and gray mottling with a glassy-to-waxy polish. Massive cryptocrystalline structure, no visible cleavage, and specific gravity around 2.5–2.8.

Identified September 15, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich groundwater replaces or fills cavities in volcanic rocks and sediments, with iron producing red and brown colors. Deposits formed at various ages, commonly during volcanic or hydrothermal activity.

Uses & applications

Used for beads, cabochons, carvings, ornaments, and lapidary material; too small and decorative here for construction use.

Geological facts

Jasper is often grouped with chalcedony but is distinguished by its opacity and abundant impurities. Color patterns can resemble breccia, landscapes, or orbicular designs.

Field identification & locations

Identify by its opaque appearance, fine texture, lack of cleavage, and ability to scratch glass; a steel blade usually does not scratch it. Common sources include India, Madagascar, Brazil, Australia, Mexico, and the western United States.