sedimentary
Calamites (Fossil)
Calamites sp. (Tracheophyta, Equisetopsida)
Hardness: 3-5 (depends on mineral replacement); Color: Tan, brown, or grey; Luster: Dull/Earthy; Structure: Internal cast displaying longitudinal ribs and nodes; Specific Gravity: varies with matrix.
- Hardness
- 3-5 (depends on mineral replacement)
- Color
- Tan, brown, or grey
- Luster
- Dull/Earthy
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Physical properties
Hardness: 3-5 (depends on mineral replacement); Color: Tan, brown, or grey; Luster: Dull/Earthy; Structure: Internal cast displaying longitudinal ribs and nodes; Specific Gravity: varies with matrix.
Formation & geological history
Formed through pith cast creation where prehistoric giant horsetails were buried in sediment during the Carboniferous period (approx. 300-360 million years ago).
Uses & applications
Scientific study, educational museum displays, and private geological collections.
Geological facts
Calamites were treelike plants that could reach heights of 30 meters; they are the ancestors of modern-day horsetails.
Field identification & locations
Identify by looking for parallel vertical ribbing and horizontal bamboo-like joints. Commonly found in coal-bearing shale and sandstone formations.
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