sedimentary

Jasper

Microcrystalline Quartz (SiO2)

Hardness: 7 on the Mohs scale. Color: Brown, yellowish-brown, red, or multicolored. Luster: Waxy to vitreous. Crystal structure: Trigonal (microcrystalline/cryptocrystalline aggregate). Cleavage: None, exhibits conchoidal fracture. Specific gravity: 2.58-2.91.

Hardness: 7 on the Mohs scale
Color: Brown, yellowish-brown, red, or multicolored
Luster: Waxy to vitreous

Identified August 5, 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-rich fluids in sedimentary environments, often involving the alteration of volcanic ash or silica precipitation in marine sediments. Geological age varies widely from Precambrian to Cenozoic.

Uses & applications

Used for making decorative objects, cabochons, carvings, and jewelry. Also collected by rockhounds and lapidary enthusiasts.

Geological facts

Jasper has been used since ancient times to create seals, signet rings, and ornamental weapons due to its toughness and ability to take a high polish. Brown varieties are sometimes referred to as picture jasper or ferruginous chert.

Field identification & locations

Can be identified in the field by its hardness (scratches glass), lack of visible crystals even under magnification, waxy luster, and conchoidal fracture. Commonly found in riverbeds, beaches, and mountainous regions worldwide.