sedimentary
Nutting Stone / Cupstone (Sandstone or Quartzite)
Sedimentary rock with anthropogenic modification (cupule)
Hardness: 6-7 (if quartzite/silica-cemented sandstone), Color: Orange-brown due to iron oxide (limonite/hematite) staining, Luster: Dull/earthy, Structure: Granular clastic.
- Luster
- Dull/earthy, Structure: Granular clastic
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Physical properties
Hardness: 6-7 (if quartzite/silica-cemented sandstone), Color: Orange-brown due to iron oxide (limonite/hematite) staining, Luster: Dull/earthy, Structure: Granular clastic.
Formation & geological history
Formed as a sedimentary deposit millions of years ago, later selected and modified by indigenous peoples to create a cupule or anvil stone used for cracking nuts or grinding pigments.
Uses & applications
Archaeological artifact, historical utility for food processing or tool manufacturing, highly valued by artifact collectors.
Geological facts
Stones featuring cup-like depressions are found worldwide and are often associated with ancient ritual practices, nutting, or fire-starting.
Field identification & locations
Identify by the presence of a smooth, deliberately pecked or ground concave depression on a naturally shaped flat rock. Found globally near historical habitation sites.
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