sedimentary
Fossiliferous Limestone
Calcium Carbonate - CaCO3
Hardness: 3 on Mohs scale; Color: Gray, tan, or white with visible fossil fragments; Luster: Dull to earthy; Structure: Biological sediment/massive; Cleavage: None (fractures irregularly).
- Hardness
- 3 on Mohs scale
- Color
- Gray, tan, or white with visible fossil fragments
- Luster
- Dull to earthy
Identified More sedimentary →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 3 on Mohs scale; Color: Gray, tan, or white with visible fossil fragments; Luster: Dull to earthy; Structure: Biological sediment/massive; Cleavage: None (fractures irregularly).
Formation & geological history
Formed in warm, shallow marine environments where skeletal fragments of marine organisms (such as coral, mollusks, or crinoids) accumulate and are lithified over millions of years.
Uses & applications
Used in construction as aggregate, in the manufacture of cement, and as a soil conditioner in agriculture. Higher quality pieces are kept by fossil collectors.
Geological facts
Limestone contains about 10% of the total volume of all sedimentary rocks. It is often the primary source of fossils for researchers studying ancient marine life.
Field identification & locations
Identify in the field by looking for visible shell fragments or small pore-like structures (bryozoans/corals). It will react and fizz when exposed to dilute hydrochloric acid.
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