Rock Identifier
Weathered fossiliferous limestone, possibly coral or stromatoporoid (Calcitic limestone, predominantly CaCO₃; fossil identity cannot be confirmed from one photograph) — sedimentary
sedimentary

Weathered fossiliferous limestone, possibly coral or stromatoporoid

Calcitic limestone, predominantly CaCO₃; fossil identity cannot be confirmed from one photograph

AI-generated identification · may be incorrect

Gray-green, fine- to medium-grained, dull to slightly earthy luster, with abundant cavities and possible fossil structures. Calcite has Mohs hardness 3, rhombohedral cleavage, and specific gravity about 2.7; it should effervesce with dilute hydrochloric acid.

Identified More sedimentary
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Physical properties

Gray-green, fine- to medium-grained, dull to slightly earthy luster, with abundant cavities and possible fossil structures. Calcite has Mohs hardness 3, rhombohedral cleavage, and specific gravity about 2.7; it should effervesce with dilute hydrochloric acid.

Formation & geological history

A carbonate sediment accumulated in a shallow marine environment and lithified, likely during the Paleozoic or Mesozoic; the rounded surface reflects later river or beach abrasion and weathering. The holes may be dissolved fossil pores, burrows, or weathered vugs.

Uses & applications

Used as aggregate, cement and lime feedstock, building stone, and occasionally as a fossil or lapidary specimen. Value is primarily educational or decorative.

Geological facts

The irregular cellular texture is consistent with a fossil-bearing carbonate, but it is not diagnostic enough to name a specific organism. Green coloration may reflect chlorite, clay minerals, or surface weathering.

Field identification & locations

Look for visible fossil outlines and test a fresh spot with dilute acid; vigorous fizz supports calcite limestone. Common in former shallow seas and limestone gravels worldwide; avoid acid testing if preservation is important.