sedimentary
Chert
Microcrystalline quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, waxy luster, conchoidal fracture, and colors ranging from grey to white and brown.
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Physical properties
Hardness of 7 on the Mohs scale, waxy luster, conchoidal fracture, and colors ranging from grey to white and brown.
Formation & geological history
Formed through the chemical precipitation of silica from aqueous solutions or the accumulation of siliceous skeletal remains.
Uses & applications
Historically used for making stone tools and weapons due to its sharp edges when fractured.
Geological facts
Chert fractures conchoidally, creating razor-sharp edges that were highly prized by ancient humans for projectile points.
Field identification & locations
Identify by its waxy luster, high hardness that scratches glass, and distinctive conchoidal fracture patterns.
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