mineral
Tumbled jasper or chert
Microcrystalline quartz (SiO₂), likely iron-stained jasper
AI-generated identification · may be incorrectOpaque tan-orange, earthy to waxy luster, fine-grained and apparently tumbled/rounded; quartz hardness is about 7 Mohs, with no visible cleavage and conchoidal fracture. Exact identification is limited by the image; it could also be a weathered chert or iron-rich chalcedony.
Identified More mineral →
Explore Tumbled jasper or chert in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Opaque tan-orange, earthy to waxy luster, fine-grained and apparently tumbled/rounded; quartz hardness is about 7 Mohs, with no visible cleavage and conchoidal fracture. Exact identification is limited by the image; it could also be a weathered chert or iron-rich chalcedony.
Formation & geological history
Forms when silica-rich groundwater replaces or fills cavities in sedimentary or volcanic rocks, with iron oxides producing the warm coloration. Formation age depends on locality and may range from Paleozoic to recent geological settings.
Uses & applications
Used as a lapidary material for cabochons, beads, carvings, and decorative objects; attractive jasper is collected rather than used structurally.
Geological facts
Jasper is an opaque variety of chalcedony or microcrystalline quartz, unlike translucent agate. The smooth shape suggests natural stream wear or human tumbling.
Field identification & locations
Common in silica-rich volcanic and sedimentary terrains worldwide, including the western United States, Madagascar, Brazil, and Australia. A glass-scratch test may support quartz hardness, but avoid damaging collectible material.
