Yellow Jasper
Silicon Dioxide (SiO₂)
Rock Type: sedimentary

Physical Properties
Hardness: 6.5-7 (Mohs); Color: Yellow, mustard, or tan; Luster: Vitreous to waxy; Structure: Microcrystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.7
Formation & Geological History
Formed through the deposition of silica from water into cavities or via the replacement of organic material. These specimens are often water-worn in riverbeds or marine environments, dating from various eras depending on the local bedrock.
Uses & Applications
Commonly used in lapidary work for cabochons, beads, and decorative carvings. It is also used as a landscape stone or metaphysical healing stone.
Geological Facts
Jasper is an opaque variety of chalcedony. The yellow color is primarily caused by inclusions of iron oxides such as goethite or limonite. Historically, it was known as a stone of protection and travel.
Field Identification & Locations
Identify by its opacity (even when held to light), smooth waxy texture when wet, and its ability to scratch glass. It is commonly found in gravel pits and beaches worldwide.
Identified on: 4/25/2026
Mode: Standard