sedimentary
Flexicalymene Trilobite Fossil
Flexicalymene meeki (Order Phacopida, Family Calymenidae)
Commonly preserved in limestone or shale; Hardness: 3-4 (calcite replacement); Color: Earthy grays, browns, and ochre; Structure: Distinctive three-lobed body division (cephalon, thorax, pygidium); Luster: Dull to earthy; Often found in a 'rolled' or enrolled defensive position.
- Hardness
- 3-4 (calcite replacement)
- Color
- Earthy grays, browns, and ochre
- Luster
- Dull to earthy
Identified More sedimentary →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Commonly preserved in limestone or shale; Hardness: 3-4 (calcite replacement); Color: Earthy grays, browns, and ochre; Structure: Distinctive three-lobed body division (cephalon, thorax, pygidium); Luster: Dull to earthy; Often found in a 'rolled' or enrolled defensive position.
Formation & geological history
Formed through permineralization in marine sedimentary environments during the Late Ordovician period (approximately 450 million years ago); notably part of the Cincinnati Arch formation.
Uses & applications
Primarily used for educational purposes, scientific research, and as highly collectible paleontological specimens for hobbyists and museums.
Geological facts
Flexicalymene is one of the most famous trilobite genera because they often enrolled into a ball for protection, much like modern pill bugs. They are the official state fossils of Ohio.
Field identification & locations
Identify by looking for rhythmic segmented ridges (thoracic segments) and a distinct central axial lobe; commonly found in the tri-state area of Ohio, Kentucky, and Indiana. Collectors should look for nodules in creek beds or road cuts containing limestone and shale layers.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Shale or Slaty Mudstone
Argillaceous sedimentary rock
sedimentary
Chert Breccia
Brecciated Chert (Microcrystalline Silica)
sedimentary
Sandstone (Quartz-rich)
Arenite (SiO2)
sedimentary
Sandstone (with man-made markings)
Arenite (composed primarily of Quartz, SiO2)
sedimentary