mineral
Chalcedony (specifically Agate or Carnelian)
Silicon Dioxide (SiO2)
Hardness: 6.5–7; Color: Orange-brown, translucent with waxy luster; Crystal Structure: Microcrystalline (trigonal); Cleavage: None/Conchoidal fracture.
- Hardness
- 6
- Color
- Orange-brown, translucent with waxy luster
Identified More mineral →
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Physical properties
Hardness: 6.5–7; Color: Orange-brown, translucent with waxy luster; Crystal Structure: Microcrystalline (trigonal); Cleavage: None/Conchoidal fracture.
Formation & geological history
Formed in cavities of volcanic rocks or sedimentary environments through the slow deposition of silica from groundwater. Often found in geode structures or as nodules.
Uses & applications
Commonly used in jewelry (cabochons), lapidary art, watch bearings, and as historical amulets/seals.
Geological facts
Carnelian was highly prized in ancient Rome and Egypt for signet rings because hot wax does not stick to it.
Field identification & locations
Identify by its waxy luster, translucency, and lack of visible grains. Found globally, especially in basalt flows, riverbeds, and beach deposits.
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Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Schist
Schist
Metamorphic
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Gypsum (variety Selenite or Alabaster)
Calcium sulfate dihydrate (CaSO4·2H2O)
Mineral
Nephrite Jade
Nephrite
Mineral/Rock
Granite
Granite (Phaneritic intrusive igneous rock)
igneous