
sedimentary
Red Jasper (Jasper)
Silicon Dioxide (SiO₂)
Hardness: 6.5-7 Mohs; Color: Brick red to brownish-red; Luster: Dull to Vitreous when polished; Crystal Structure: Trigonal/Microcrystalline; Cleavage: None (Conchoidal fracture); Specific Gravity: 2.58-2.91
- Hardness
- 6
- Color
- Brick red to brownish-red
- Luster
- Dull to Vitreous when polished
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Physical properties
Hardness: 6.5-7 Mohs; Color: Brick red to brownish-red; Luster: Dull to Vitreous when polished; Crystal Structure: Trigonal/Microcrystalline; Cleavage: None (Conchoidal fracture); Specific Gravity: 2.58-2.91
Formation & geological history
Formed through the deposition of silica from water-rich environments, often within sedimentary beds or in hydrothermal veins where fine-grained silica mingles with iron oxide (giving it the red color). It can range from Precambrian to modern ages.
Uses & applications
Used widely in lapidary work for cabochons, beads, and jewelry. It is also used as a decorative stone in mosaics, aquarium gravel, and as a spiritual gemstone in metaphysical communities.
Geological facts
Jasper is highly opaque compared to other varieties of chalcedony. Historically, it was known as the 'supreme nurturer' across various ancient cultures and was used for amulets in Ancient Egypt.
Field identification & locations
Identify by its rich red color, extreme hardness (it will scratch glass), and smooth, waxy feel when wet. Often found in riverbeds or gravel deposits near volcanic or sedimentary regions. Common in the Western US, South Africa, and Brazil.
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