sedimentary

Hag Stone

Sandstone or Limestone with Solution Holes (Bioturbation/Erosion)

AI-generated identification · may be incorrect

Hardness: 3-7 (depending on mineralogy); Color: Tan, brown, grey; Luster: Dull/Earthy; Structure: Clastic or Biogenic; Features distinctive natural boreholes.

Hardness: 3-7 (depending on mineralogy)
Color: Tan, brown, grey
Luster: Dull/Earthy

Identified June 19, 2026More sedimentary →

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Physical properties

Hardness: 3-7 (depending on mineralogy); Color: Tan, brown, grey; Luster: Dull/Earthy; Structure: Clastic or Biogenic; Features distinctive natural boreholes.

Formation & geological history

Formed through sedimentary deposition followed by chemical weathering or biological erosion. Holes are often created by pholads (boring mollusks) in marine environments or the localized dissolution of softer mineral pockets (nodules) by acidic water.

Uses & applications

Used primarily as decorative garden stones, talismans in folk magic (historically believed to protect against nightmares and witches), and as natural artifacts for collectors.

Geological facts

Also known as Witch Stones, Adder Stones, or Hole-ey Stones. Folklore suggests that looking through the hole allows a person to see into the fairy realm or reveal invisible spirits.

Field identification & locations

Identify by a naturally occurring hole that penetrates completely through the stone. Commonly found in riverbeds, glacial till, or coastal areas where churning water and sand accelerate the boring process.