mineral

Yellow jasper (likely iron-stained chalcedony)

Jasper, an opaque microcrystalline variety of quartz (SiO₂); likely iron-oxide colored

AI-generated identification · may be incorrect

Mohs hardness 6.5–7; yellow, ochre, and cream mottling with a waxy to dull luster. Microcrystalline, with no visible cleavage; specific gravity about 2.6.

Identified September 29, 2026More mineral →

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Physical properties

Mohs hardness 6.5–7; yellow, ochre, and cream mottling with a waxy to dull luster. Microcrystalline, with no visible cleavage; specific gravity about 2.6.

Formation & geological history

Forms as silica-rich chalcedony in cavities and fractures, with iron oxides producing yellow coloration. It can occur in rocks of many ages and settings.

Uses & applications

Used for beads, cabochons, carvings, and decorative objects; common pieces are primarily valued as lapidary material.

Geological facts

Jasper is opaque, unlike many varieties of agate, though the names can overlap for patterned chalcedony.

Field identification & locations

A smooth, opaque surface and hardness sufficient to resist scratching by a steel knife suggest jasper; yellow color alone cannot confirm the identification. Found worldwide in silica-rich deposits.