sedimentary
Fossil Plant Impression (Calamites)
Calamites sp. (Tracheophyta: Equisetopsida)
Hardness: 2.5-4 (Mohs), Color: Light gray to tan, Luster: Dull/Earthy, Structure: Characterized by distinctive vertical parallel ridges and grooves (nodes and internodes) on a cylindrical cast or impression.
- Hardness
- 2
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Physical properties
Hardness: 2.5-4 (Mohs), Color: Light gray to tan, Luster: Dull/Earthy, Structure: Characterized by distinctive vertical parallel ridges and grooves (nodes and internodes) on a cylindrical cast or impression.
Formation & geological history
Formed during the Carboniferous period (approx. 300-360 million years ago) from the trunk of giant horsetail plants in swamplands. The organic material was replaced by fine-grained sediment or compressed into coal-bearing strata.
Uses & applications
Primarily used for scientific research, paleontology education, and as a collectible for fossil enthusiasts.
Geological facts
Calamites were prehistoric trees that grew up to 100 feet tall. They are the ancient ancestors of the modern horsetail plant (Equisetum), which rarely exceeds 3-4 feet today.
Field identification & locations
Identify in the field by looking for 'corduroy' or ribbed patterns in shale or sandstone near coal seams. Common in the Appalachian Mountains (USA), UK, and Germany.
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