sedimentary
Chert
Microcrystalline Quartz (SiO2)
Hardness: 7 on Mohs scale; Color: typically dull pink, orange, or reddish-brown in this specimen; Luster: waxy to dull; Structure: microcrystalline; Cleavage: none, conchoidal fracture.
- Hardness
- 7 on Mohs scale
- Luster
- waxy to dull
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Physical properties
Hardness: 7 on Mohs scale; Color: typically dull pink, orange, or reddish-brown in this specimen; Luster: waxy to dull; Structure: microcrystalline; Cleavage: none, conchoidal fracture.
Formation & geological history
Formed via the accumulation of silica-rich organic remains (like radiolaria or diatoms) or chemical precipitation in marine environments; age varies from Precambrian to Cenozoic.
Uses & applications
Historically used for stone tools/weapons due to sharp edges; commonly used today in road construction, landscaping, and high-polishing for aquarium gravel or jewelry.
Geological facts
Flint is a variety of chert. It was one of the most important minerals for early humans to create fire and sharp cutting tools.
Field identification & locations
Check for conchoidal (shell-like) fractures and extreme hardness (it will scratch glass). Commonly found in stream beds or limestone deposits.
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