sedimentary

Hag Stone

Perforated Sedimentary Rock / Flint / Limestone

Hardness varies from 3 to 7 depending on the base mineral (often flint, quartz, or limestone); colors range from grey, white, to brown; dull to waxy luster; amorphous or microcrystalline crystal structure; irregular fracture; specific gravity around 2.6 to 2.7.

Identified August 5, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed naturally through intense wave action, weathering, and the continuous flow of water or sand over centuries, which erodes softer mineral inclusions out of a harder host rock, leaving a hole completely through the stone.

Uses & applications

Historically used as a protective talisman, amulet, or charm in folklore and witchcraft (often hung on doors, windows, or bedposts to ward off negative energy or nightmares); also valued as a curiosity by collectors.

Geological facts

Also known as adder stones, hole stones, witch stones, or holy stones, they feature prominently in European folklore. In maritime tradition, looking through the hole was believed to allow the viewer to see fairies, spirits, or hidden treasures.

Field identification & locations

Found commonly along beaches, riverbanks, and coastlines where water erosion is active. Collectors look specifically for rocks naturally pierced all the way through without human intervention.

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Sedimentary Sandstone

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Banded Siltstone / Mudstone Pebble

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