sedimentary
Hag Stone
Porous sedimentary rock (typically Flint, Chert, or Sandstone) with naturally occurring holes
Hardness: 6.5-7 (if silica-based like Flint), Color: Brown, gray, and earthy tones with white mineral accents, Luster: Dull to waxy, Structure: Microcrystalline with smooth-edged natural perforations, Cleavage: None/Conchoidal.
- Hardness
- 6
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Physical properties
Hardness: 6.5-7 (if silica-based like Flint), Color: Brown, gray, and earthy tones with white mineral accents, Luster: Dull to waxy, Structure: Microcrystalline with smooth-edged natural perforations, Cleavage: None/Conchoidal.
Formation & geological history
Formed through the process of water erosion over thousands of years; often found in coastal or fluvial environments where boring organisms like piddock clams or abrasive currents drill through softer parts of the rock.
Uses & applications
Primarily used as a lucky charm, in jewelry as natural pendants, or as a decorative collector's item in spiritual practices.
Geological facts
Also known as 'Odin stones' or 'Witch stones,' folklore suggests they protect against nightmares and the 'Evil Eye' if hung above a bed or doorway.
Field identification & locations
Identify by a hole that goes completely through the stone, smoothed by water; commonly found along beaches in the UK (Dorset coast) and the US (Great Lakes or Northeast coast).
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