sedimentary (chemical/biological origin)

Red Jasper (Plum or Brick variety)

Silicon Dioxide (SiO2) with iron oxide inclusions (Hematite)

Hardness: 6.5-7 (Mohs scale); Color: Deep brownish-red/maroon; Luster: Dull to waxy; Crystal structure: Microcrystalline (trigonal); Cleavage: None (conchoidal fracture); Specific gravity: 2.58-2.91

Hardness: 6
Color: Deep brownish-red/maroon
Luster: Dull to waxy

Identified March 9, 2026More sedimentary (chemical/biological origin) →

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Physical properties

Hardness: 6.5-7 (Mohs scale); Color: Deep brownish-red/maroon; Luster: Dull to waxy; Crystal structure: Microcrystalline (trigonal); Cleavage: None (conchoidal fracture); Specific gravity: 2.58-2.91

Formation & geological history

Formed from the deposition of silica in hydrothermal veins or sedimentary environments. Its deep red color is caused by high concentrations of iron oxide (hematite) dispersed through the quartz matrix. Can range from Precambrian to modern formations.

Uses & applications

Used primarily as an ornamental stone, for lapidary work (cabochons, beads), and in metaphysical collecting. Historically used for making tools and seals due to its hardness.

Geological facts

Red jasper was known as the 'rain bringer' in some ancient cultures. It is a dense, opaque variety of chalcedony that never transmits light, even at thin edges.

Field identification & locations

Identify in the field by its deep red color, conchoidal fracture patterns, and its ability to scratch glass while resisting a steel blade. Commonly found in South Africa, Brazil, India, and the southwestern USA.

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sedimentary (chemical/biological origin)

Jasper (Wonderstone/Banded Jasper)

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sedimentary (chemical/biological origin) or volcanic-related metamorphic

Chert (and Flint)

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Limestone (specifically Marl or Chalk)

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Note: Item is not a geological specimen

Homo sapiens (Dermal Appendage: Pilus)

Organic / Biological