sedimentary
Trilobite Fossil
Trilobita (Class), likely Phacopid or Asaphid order
Hardness: 3-4 (matrix usually limestone or shale); Color: Brownish to grey; Luster: Variable, often dull but can be vitreous; Structure: Symmetrical three-lobed exoskeleton of calcified chitin.
- Hardness
- 3-4 (matrix usually limestone or shale)
- Color
- Brownish to grey
- Luster
- Variable, often dull but can be vitreous
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Physical properties
Hardness: 3-4 (matrix usually limestone or shale); Color: Brownish to grey; Luster: Variable, often dull but can be vitreous; Structure: Symmetrical three-lobed exoskeleton of calcified chitin.
Formation & geological history
Formed through permineralization in marine environments during the Paleozoic era, roughly 521 to 252 million years ago. Usually found in shale, siltstone, or limestone matrix.
Uses & applications
Primarily used for scientific research, educational purposes, and by hobbyist collectors.
Geological facts
Trilobites are one of the earliest known groups of arthropods and survived for nearly 300 million years through multiple mass extinction events before finally going extinct in the Permian period.
Field identification & locations
Identify by looking for the distinct cephalon (head), thorax (segmented body), and pygidium (tail) segments. Commonly found in quarries and road cuts with exposed Paleozoic strata.
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