sedimentary

Jasper with Quartz Veining

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Hardness: 6.5-7 on Mohs scale; Color: Reddish-brown with white/tan veins; Luster: Vitreous to waxy; Crystal structure: Trigonal (Microcrystalline); Cleavage: None (conchoidal fracture); Specific gravity: 2.58-2.91

Hardness: 6
Color: Reddish-brown with white/tan veins
Luster: Vitreous to waxy

Identified March 9, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the deposition of silica from water-rich fluids in volcanic or sedimentary environments. The veins represent secondary silica (Quartz) infilling fractures in the host rock. Geological age can range from Precambrian to Cenozoic.

Uses & applications

Used primarily for lapidary work, jewelry (cabochons), interior decoration, and as a popular specimen for rock hounds and collectors.

Geological facts

Jasper is an impure variety of silica, usually containing iron oxides which give it the red/brown color. The 'brecciated' or veined appearance occurs after the original rock fractures and is 'healed' by new mineral growth.

Field identification & locations

Identify in the field by its high hardness (it will scratch glass), smooth waxy feel when wet, and lack of visible grains. Commonly found in riverbeds, desert washes, and volcanic deposits in the Western United States and India.

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