sedimentary
Hag Stone
Perforated Flint
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, vitreous to dull luster, cryptocrystalline structure, conchoidal fracture, and white to grey or black coloration.
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Physical properties
Hardness of 7 on the Mohs scale, vitreous to dull luster, cryptocrystalline structure, conchoidal fracture, and white to grey or black coloration.
Formation & geological history
Formed through the chemical precipitation of silica in chalk or limestone marine environments over millions of years, with holes created by acid erosion or softer inclusions weathering away.
Uses & applications
Traditionally used as a protective talisman or amulet in folklore, and collected as a curiosity by beachcombers.
Geological facts
Also known as adder stones, witch stones, or hole stones, they were historically believed to protect against evil magic and allow the wearer to see through faerie realms.
Field identification & locations
Identified by naturally occurring holes completely piercing the rock, commonly found along beaches, riverbeds, and chalk-rich coastal areas.
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