Jasper

Physical Properties

Hardness: 6.5–7 (Mohs scale), Color: Green and brown bands/mottling, Luster: Vitreous to waxy, Crystal Structure: Microcrystalline (Trigonal), Cleavage: None, Specific Gravity: 2.58–2.91

Formation & Geological History

Formed through the accumulation of fine silica-rich sediments or volcanic ash that undergoes lithification. This specimen likely formed in an environment with fluctuating mineral content, causing the layered or banded appearance.

Uses & Applications

Commonly used for decorative ornaments, lapidary work (tumbling/polishing), jewelry (cabochons), and as a collector's specimen.

Geological Facts

Jasper is an opaque variety of chalcedony. The name comes from the Old French 'jaspre', meaning 'spotted or speckled stone'. It has been used as a gemstone since antiquity.

Field Identification & Locations

Identify in the field by its hardness (will scratch glass), opaque nature, and smooth, conchoidal fracture. Often found as rounded river stones or in desert washes.

Identified on: 4/21/2026

Mode: Standard