sedimentary

Jasper

Jasper (Silica/Silicon Dioxide, SiO2)

Hardness: 6.5-7 on Mohs scale; Color: Multicolored with red, tan, and creamy white bands; Luster: Vitreous to waxy; Crystal structure: Microcrystalline (Trigonal); Cleavage: None (Conchoidal fracture); Specific gravity: 2.58-2.91

Hardness: 6
Color: Multicolored with red, tan, and creamy white bands
Luster: Vitreous to waxy

Identified June 28, 2026More sedimentary →

Explore Jasper in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Formed through the deposition of silica in sedimentary environments or hydrothermal veins. This specimen shows a tumbled or polished surface, often found in ancient riverbeds or volcanic ash deposits where silica-rich fluids permeate porous rock.

Uses & applications

Commonly used in jewelry for cabochons and beads, as well as decorative items, ornaments, and pocket stones for collectors.

Geological facts

Jasper is an opaque variety of chalcedony. The red coloration seen in this specimen is typically caused by iron inclusions. It has been used since antiquity for seals, amulets, and architectural ornamentation.

Field identification & locations

Identify in the field by its opacity (unlike translucent agate), high hardness (cannot be scratched by a steel nail), and smooth, waxy feel when polished. Widely found in the Western United States, Brazil, and India.