sedimentary

Yellow Jasper

Silicon Dioxide (SiO2)

Hardness: 6.5-7 Mohs; Color: Mustard yellow to brownish-yellow; Luster: Dull or waxy; Crystal Structure: Microcrystalline (trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.58-2.91

Hardness: 6
Color: Mustard yellow to brownish-yellow
Luster: Dull or waxy

Identified July 1, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 Mohs; Color: Mustard yellow to brownish-yellow; Luster: Dull or waxy; Crystal Structure: Microcrystalline (trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.58-2.91

Formation & geological history

Formed through the deposition of silica from water-rich environments, often in sedimentary or volcanic rock cavities. Its coloration comes from fine-grained iron inclusions (Goethite). Found in deposits spanning various geological eras.

Uses & applications

Commonly used for lapidary work including cabochons, beads, and carvings. Also used as a decorative stone and in crystal healing practices.

Geological facts

Jasper was a favorite gem in the ancient world; its name can be traced back in Arabic, Persian, Hebrew, Assyrian, Greek, and Latin. Yellow jasper is specifically noted for its high iron content which gives it its mustard-like hue.

Field identification & locations

Identify by its hardness (will scratch glass), opaque nature, and smooth, waxy feel when wet or polished. Often found in riverbeds, desert landscapes, and regions with ancient volcanic activity.