mineral
Carnelian
Carnelian (Cryptocrystalline Quartz, SiO2)
Hardness: 6.5-7 on Mohs scale; Color: Orange, red, brownish-red; Luster: Vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.58-2.64.
- Hardness
- 6
- Color
- Orange, red, brownish-red
- Luster
- Vitreous to waxy
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Physical properties
Hardness: 6.5-7 on Mohs scale; Color: Orange, red, brownish-red; Luster: Vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; Specific Gravity: 2.58-2.64.
Formation & geological history
Formed in cavities and veins of volcanic rocks (basalt/rhyolite) through the deposition of silica from groundwater; its red-orange tint comes from iron oxide impurities.
Uses & applications
Commonly used in jewelry (beads, cabochons), carvings, and seal stones; also highly valued by collectors as a pocket stone or tumbled specimen.
Geological facts
Carnelian was used widely in ancient Rome and Greece for signet rings because hot wax does not stick to it. It was also believed by ancient Egyptians to provide protection for the soul.
Field identification & locations
Identify by its translucent reddish-orange hue and waxy luster when polished. It lacks the distinct banding of agate but belongs to the same chalcedony family. Found globally in India, Brazil, and Uruguay.
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Schist
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Metamorphic
Epidote
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metamorphic
Gypsum (variety Selenite or Alabaster)
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Mineral
Nephrite Jade
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Mineral/Rock