Sedimentary

Hag Stone

Naturally holed stone (typically sedimentary rock such as flint, limestone, or sandstone)

AI-generated identification · may be incorrect

Physical properties vary depending on the host rock type, but generally feature a naturally occurring hole passing entirely through the stone. Appearance is often weathered, rounded, or irregular with a dull luster.

Identified May 31, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed by water erosion, often in marine or river environments, where softer parts of the stone or inclusions are worn away faster than the surrounding rock, eventually creating a hole.

Uses & applications

Primarily used as amulets, talismans, or decorative items. Historically believed to offer protection against witchcraft or the evil eye, and used to see 'faeries' or other realms when looking through the hole.

Geological facts

Also known as a witch stone, adder stone, snake's egg, hex stone, or fairy stone. They have a long history in European folklore, particularly in Celtic and Norse traditions.

Field identification & locations

Identify by a naturally occurring hole through the stone, usually found on beaches, riverbeds, or areas with significant water erosion. Check that the hole looks natural and not drilled.