mineral
Carnelian
Silicon Dioxide (SiO2) with iron oxide impurities
AI-generated identification · may be incorrectHardness: 6.5-7 (Mohs); Color: Reddish-orange, amber, brownish-red; Luster: Vitreous to waxy; Crystal structure: Trigonal (microcrystalline/cryptocrystalline); Cleavage: None; Specific Gravity: 2.58-2.64
- Hardness
- 6
- Color
- Reddish-orange, amber, brownish-red
- Luster
- Vitreous to waxy
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Physical properties
Hardness: 6.5-7 (Mohs); Color: Reddish-orange, amber, brownish-red; Luster: Vitreous to waxy; Crystal structure: Trigonal (microcrystalline/cryptocrystalline); Cleavage: None; Specific Gravity: 2.58-2.64
Formation & geological history
Formed in volcanic cavities or sedimentary environments where silica-rich fluids cool and crystallize at low temperatures. Common in geodes and ancient riverbeds.
Uses & applications
Used primarily in jewelry as beads, cabochons, and carved seals. Also popular as a pocket stone for collectors and in metaphysical practices.
Geological facts
Carnelian was used by ancient Egyptians as a protective stone for the dead and by Romans to make engraved signet rings because hot wax does not stick to it.
Field identification & locations
Identify by its translucent reddish hue and lack of visible crystal structure (unlike macrocrystalline quartz). Commonly found in Brazil, India, Uruguay, and Madagascar.
