Rock Identifier
Tumbled jasper pebble (Jasper, an opaque microcrystalline variety of quartz (SiO₂), commonly colored by iron oxides and hydroxides) — mineral
mineral

Tumbled jasper pebble

Jasper, an opaque microcrystalline variety of quartz (SiO₂), commonly colored by iron oxides and hydroxides

AI-generated identification · may be incorrect

Typically hardness 6.5–7 Mohs, opaque, orange-red to brown with cream weathering surfaces, earthy to vitreous luster, and no visible cleavage; compact cryptocrystalline texture. The specimen appears naturally rounded or tumbled and iron-stained, with possible small greenish mineral inclusions.

Identified More mineral
Explore Tumbled jasper pebble in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

Physical properties

Typically hardness 6.5–7 Mohs, opaque, orange-red to brown with cream weathering surfaces, earthy to vitreous luster, and no visible cleavage; compact cryptocrystalline texture. The specimen appears naturally rounded or tumbled and iron-stained, with possible small greenish mineral inclusions.

Formation & geological history

Forms when silica-rich fluids replace or cement volcanic ash, sediment, or cavities, with iron producing the red-orange color. Its precise geological age and locality cannot be determined from the photograph; jasper occurs in many ancient volcanic and sedimentary terrains.

Uses & applications

Used for cabochons, beads, carvings, ornaments, and lapidary specimens; durable pieces are also used decoratively. Common tumbled material generally has modest value.

Geological facts

Jasper is not a single mineral species but a rock composed mainly of microcrystalline quartz. Color patterns reflect impurities, brecciation, fluid alteration, and weathering.

Field identification & locations

Identify it by its opaque appearance, fine texture, lack of cleavage, red-orange iron staining, and ability to scratch ordinary glass. Common sources include Oregon, Idaho, California, Utah, Arizona, Brazil, India, and Madagascar.