sedimentary

Hag Stone (Banded Chert or Limestone with Borehole)

Microcrystalline Quartz (Chert) or Calciferous Siltstone (CaCO3/SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (if chert) or 3-4 (if limestone); Color: Grey, brown, tan, and cream banding; Luster: Dull/Waxy; Structure: Cryptocrystalline/Massive; Presence of a natural 'hag hole' caused by erosion.

Hardness: 6
Color: Grey, brown, tan, and cream banding
Luster: Dull/Waxy

Identified March 22, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the accumulation of silica-rich or carbonate-rich sediment in prehistoric marine environments, later shaped by mechanical or biological erosion (such as 'piddock' boring bivalves or water action) to create a hole.

Uses & applications

Primarily used as a lucky charm, protective talisman in folklore, or as an ornamental/educational piece for rock collectors and beachcombers.

Geological facts

In European folklore, hag stones were believed to protect against witchcraft, nightmares, and the 'evil eye' because 'magic cannot cross running water,' and the hole was created by water.

Field identification & locations

Identify in the field by looking for stones with naturally occurring, smooth-edged holes through them. Commonly found on pebble beaches or in riverbeds where high water energy occurs.