sedimentary
Flint
Silicon dioxide (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, typically dark grey to black or brown, waxy or vitreous luster, and exhibits conchoidal fracture.
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Physical properties
Hardness of 7 on the Mohs scale, typically dark grey to black or brown, waxy or vitreous luster, and exhibits conchoidal fracture.
Formation & geological history
Formed through the chemical replacement of calcium carbonate by silica-rich solutions within chalk or limestone formations during the Cretaceous period.
Uses & applications
Historically used for producing sparks to start fires and crafting stone tools; currently used in abrasives, ceramics, and lapidary.
Geological facts
Flint breaks with extremely sharp edges, making it historically invaluable worldwide for ancient weaponry and tools.
Field identification & locations
Identify it by its smooth, waxy feel, conchoidal fracture patterns, and ability to scratch glass easily. Commonly found inside chalk and limestone deposits globally.
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Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
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