sedimentary
Chert (Flint fragment)
Microcrystalline Quartz (SiO2)
AI-generated identification · may be incorrectHardness 7 on Mohs scale; conchoidal fracture; dull to waxy luster; gray to tan color with a weathered exterior cortex.
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Physical properties
Hardness 7 on Mohs scale; conchoidal fracture; dull to waxy luster; gray to tan color with a weathered exterior cortex.
Formation & geological history
Formed via chemical or biochemical precipitation of silica in marine sediment environments, often replacing carbonate rocks.
Uses & applications
Historically utilized for primitive cutting tools and fire-striking; used currently in construction aggregate and as decorative stone.
Geological facts
Flint produces pyrophoric sparks when struck against high-carbon steel, making it essential to historical fire-making and flintlock firearms.
Field identification & locations
Recognized in the field by smooth conchoidal fractures, ability to scratch glass easily, and a distinct chalky weathering patina.
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