sedimentary
Flint
SiO2 (Microcrystalline Quartz)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, typically grey, brown, or black with a waxy to vitreous luster and conchoidal fracture.
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Physical properties
Hardness of 7 on the Mohs scale, typically grey, brown, or black with a waxy to vitreous luster and conchoidal fracture.
Formation & geological history
Forms by chemical replacement of limestone or chalk in marine environments over millions of years.
Uses & applications
Historically used for making stone tools and fire-starting; currently utilized in abrasives and decorative landscaping.
Geological facts
Prehistoric humans heavily relied on flint due to its ability to fracture into extremely sharp edges.
Field identification & locations
Identified easily by its smooth, weathered outer cortex, conchoidal fracture surfaces, and extreme hardness.
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