sedimentary
Hag Stone
Flint / Chert / Limestone concretion with a natural hole
Hardness varies depending on material (usually 3-7 on Mohs scale). Color is typically gray, beige, white, or brown. Luster is dull to earthy. Irregular shape, often smooth due to water erosion, with one or more naturally occurring holes.
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Physical properties
Hardness varies depending on material (usually 3-7 on Mohs scale). Color is typically gray, beige, white, or brown. Luster is dull to earthy. Irregular shape, often smooth due to water erosion, with one or more naturally occurring holes.
Formation & geological history
Formed through natural erosion by water, wind, or the boring activity of bivalves or sponges over thousands of years. Usually found in sedimentary deposits like limestone or chalkbeds, often weathered out and transported by water.
Uses & applications
Mainly collected for folklore and spiritual purposes. Used as protective amulets, good luck charms, or decorative items. No significant industrial use.
Geological facts
Also known as adder stones, witch stones, or holy stones. In folklore, they are believed to ward off evil, protect against witches, and allow one to see into the fairy realm when looking through the hole.
Field identification & locations
Identify by finding a naturally occurring hole entirely through a stone. Commonly found on beaches or in riverbeds. Valued by collectors of folklore items and natural curiosities.
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