sedimentary
Chert / Flint
Microcrystalline quartz (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, waxy to vitreous luster, conchoidal fracture, and colors ranging from grey and brown to white.
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Physical properties
Hardness of 7 on the Mohs scale, waxy to vitreous luster, conchoidal fracture, and colors ranging from grey and brown to white.
Formation & geological history
Formed through the chemical precipitation of silica from seawater or the replacement of limestone by silica-rich solutions.
Uses & applications
Historically used for making stone tools and fire-starting; currently utilized in abrasive grit and decorative landscaping.
Geological facts
Chert breaks with extremely sharp edges, making it the primary material for prehistoric projectile points and blades.
Field identification & locations
Identify by its distinct conchoidal fracture, waxy luster, and high hardness that scratches glass.
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