sedimentary
Hag Stone
Perforated sedimentary rock (typically sandstone or limestone)
AI-generated identification · may be incorrectHardness varies from 3 to 7 depending on mineral content; colors range from tan to grey; dull luster; smooth texture from water erosion.
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Physical properties
Hardness varies from 3 to 7 depending on mineral content; colors range from tan to grey; dull luster; smooth texture from water erosion.
Formation & geological history
Formed through natural water erosion where acidic water or wave action dissolves softer minerals or drills through weak spots in rocks over thousands of years.
Uses & applications
Historically used as a protective amulet against evil spirits, nightmares, and witchcraft; valued by collectors and modern folklorists.
Geological facts
Also known as adder stones, mare rocks, or hole stones, they are traditionally believed in folklore to grant the ability to see through magical illusions when peered through.
Field identification & locations
Found along riverbanks, lakeshores, and beaches where wave or current action continuously tumbles and bores into sedimentary rocks.
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