Jasper

Physical Properties

Hardness: 6.5 to 7 (Mohs scale), Color: Brown, tan, reddish-brown, Luster: Vitreous to dull, Crystal structure: Trigonal (microcrystalline), Cleavage: None/Conchoidal fracture, Specific gravity: 2.58 to 2.91

Formation & Geological History

Formed through the deposition of silica from water or hydrothermal fluids, often in volcanic or sedimentary environments. It is a microcrystalline variety of quartz that gets its color from high iron content.

Uses & Applications

Commonly used as a gemstone for jewelry (cabochons, beads), decorative ornaments, and by lapidary hobbyists for polishing.

Geological Facts

Jasper is an opaque variety of chalcedony. The name 'Jasper' is derived from the Greek word 'iaspis', meaning spotted stone. It has been used for thousands of years in seals and jewelry.

Field Identification & Locations

Identify by its opacity, conchoidal fracture (smooth, curved breaks), and hardness (it will scratch glass). It is commonly found in river beds, beaches, and desert regions worldwide, notably in India, Brazil, and the USA.

Identified on: 5/15/2026

Mode: Standard