Yellow Jasper

Physical Properties

Hardness: 6.5-7 (Mohs scale); Color: Yellow-brown, mustard, or amber; Luster: Vitreous to waxy; Structure: Microcrystalline quartz; Cleavage: None (conchoidal fracture); Specific Gravity: 2.58–2.91

Formation & Geological History

Formed from the deposition of silica-rich fluids in volcanic ash or fine-grained sediments through a process of silicification. The yellow color is primarily due to iron oxide (goethite) inclusions.

Uses & Applications

Commonly used for lapidary work, cabochons, beads for jewelry, and as an ornamental ground stone or collectible specimen.

Geological Facts

Jasper is an opaque variety of chalcedony. Historically, it was known as a 'nurturing stone' and was used in ancient civilizations for protective amulets.

Field Identification & Locations

Identify by its opacity, conchoidal fracture (smooth, shell-like breaks), and its inability to be scratched by a steel knife. Commonly found in riverbeds or desert regions globally.

Identified on: 4/21/2026

Mode: Standard