mineral

Likely tumbled yellow jasper or iron-rich chert

Microcrystalline quartz (SiO₂), colored by iron oxides

AI-generated identification · may be incorrect

Opaque mustard-yellow to brown, waxy to dull luster, massive microcrystalline structure, no visible cleavage, conchoidal fracture; hardness about 6.5–7 Mohs and specific gravity about 2.6.

Identified September 7, 2026More mineral →

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Physical properties

Opaque mustard-yellow to brown, waxy to dull luster, massive microcrystalline structure, no visible cleavage, conchoidal fracture; hardness about 6.5–7 Mohs and specific gravity about 2.6.

Formation & geological history

Forms when silica-rich fluids replace or cement sediment, with iron oxides producing the yellow color; typically associated with sedimentary or volcanic environments, ranging from Precambrian to younger deposits.

Uses & applications

Used as an ornamental and lapidary stone for cabochons, beads, carvings, and tumbled specimens; usually not important for construction.

Geological facts

Jasper is technically a variety of opaque, impure chalcedony or chert. The rounded shape and smooth surface indicate tumbling or natural abrasion, while the granular interior is consistent with jasper rather than a transparent crystal.

Field identification & locations

Identify by its opaque body, fine texture, waxy surface, lack of cleavage, and resistance to scratching; a steel file should generally not scratch it. Common sources include India, Madagascar, Brazil, Australia, and the western United States.