sedimentary
Eyestone Flint
SiO2 (Microcrystalline Quartz / Flint)
Hardness of 7 on the Mohs scale, typically white to grey or brown with concentric banding resembling an eye, waxy to vitreous luster, amorphous or microcrystalline crystal structure, conchoidal fracture with no true cleavage.
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Physical properties
Hardness of 7 on the Mohs scale, typically white to grey or brown with concentric banding resembling an eye, waxy to vitreous luster, amorphous or microcrystalline crystal structure, conchoidal fracture with no true cleavage.
Formation & geological history
Formed during the Cretaceous period through the replacement of calcium carbonate in chalk with silica-rich fluids precipitating in nodules, later exposed and rounded by wave action on beaches.
Uses & applications
Commonly collected as a unique talisman or curiosity by beachcombers, historically used for making primitive tools and fire-starting.
Geological facts
In folklore, eye agates and eye flints are often called 'hag stones' or 'evil eye stones' and were traditionally used as protective amulets against negative energy.
Field identification & locations
Found along chalk-rich coastal areas and beaches, identified by its smooth waterworn surface and distinct eye-like circular banding patterns.
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