sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with Goethite/Iron oxide inclusions

Hardness: 6.5-7 (Mohs scale), Color: Mustard yellow to golden brown with dark banding, Luster: Vitreous to waxy, Structure: Cryptocrystalline (Microcrystalline Quartz), Cleavage: None (Conchoidal fracture), Specific Gravity: 2.58-2.91

Hardness: 6

Identified March 14, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the process of silicification, where silica-rich fluids permeate porous sedimentary rocks or volcanic ash. The yellow color typically comes from goethite or other iron hydroxide inclusions. Geological age varies by site, from Precambrian to recent deposits.

Uses & applications

Commonly used in lapidary work for cabochons, beads, and ornamental carvings. Also used as a decorative stone in landscaping and for spiritual/new age collections as a 'nurturing' stone.

Geological facts

Jasper is an opaque variety of chalcedony. The name comes from the Greek word 'iaspis', meaning 'spotted stone.' Large deposits of yellow jasper are famously found in the 'Deserts of Egypt' and have been used for amulets since antiquity.

Field identification & locations

Identify by its opacity (unlike translucent agate) and smooth, glass-like fracture. It feels denser than average river stones. Often found in dry riverbeds, deserts, or coastal gravels. Collectors should look for unique banding or 'picture' patterns.

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