sedimentary

Yellow Jasper

Silicon Dioxide (SiO2)

Hardness: 6.5-7 Mohs; Color: Yellow-olive, mustard; Luster: Vitreous to waxy; Crystal Structure: Hexagonal (microcrystalline/cryptocrystalline); Cleavage: None; Specific Gravity: 2.58-2.91

Hardness: 6
Color: Yellow-olive, mustard
Luster: Vitreous to waxy

Identified June 18, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 Mohs; Color: Yellow-olive, mustard; Luster: Vitreous to waxy; Crystal Structure: Hexagonal (microcrystalline/cryptocrystalline); Cleavage: None; Specific Gravity: 2.58-2.91

Formation & geological history

Formed via the accumulation of silica from ash or volcanic sediment in hydrothermal environments; the yellow color is caused by iron (goethite) inclusions.

Uses & applications

Commonly used for lapidary work, decorative cabochons, metaphysical crystals, and landscaping ornamentation.

Geological facts

Jasper is an opaque variety of chalcedony. It has been used since antiquity for royal seals and amulets, often associated with protection and stability.

Field identification & locations

Identify by its opacity (it will not let light through like agate), waxy appearance when wet, and smooth conchoidal fracture. Found frequently in riverbeds and coastal areas.