sedimentary

Hag Stone

Porous Quartz or Chert Pebble (SiO2)

Hardness: 6.5-7 (Mohs scale); Color: White, cream, or light tan; Luster: Dull to waxy; Crystal Structure: Microcrystalline (Cryptocrystalline); Cleavage: None (conchoidal fracture); Features a natural perforation or hole.

Hardness: 6
Color: White, cream, or light tan
Luster: Dull to waxy

Identified June 3, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the erosion of sedimentary rocks (like flint or chert) by moving water. Holes are typically created by the boring of pholad shells or long-term water and grit erosion in riverbeds or coastal zones.

Uses & applications

Primarily used as a lucky charm, in folk magic, jewelry, and as a decorative collector's item.

Geological facts

According to European folklore, hag stones (also called Adder Stones) were believed to protect against the 'Evil Eye,' night terrors, and witchcraft. Looking through the hole was said to reveal the invisible world of fairies.

Field identification & locations

Identify by looking for a naturally occurring hole that passes entirely through the stone. Commonly found on beaches, especially in the UK and along the Baltic coast.