fossil

Fossiliferous Limestone / Petrifaction

Sedimentary rock with fossil inclusions / Calcium Carbonate (CaCO3)

AI-generated identification · may be incorrect

Hardness: 3-4 on Mohs scale; Color: Grayish-brown, tan, and dark earthy tones; Luster: Dull to earthy; Texture: Fine-grained matrix with preserved fossilized texture and fibrous mineral structures; Specific Gravity: ~2.5-2.7.

Hardness: 3-4 on Mohs scale
Color: Grayish-brown, tan, and dark earthy tones
Luster: Dull to earthy

Identified July 26, 2026More fossil →

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Physical properties

Formation & geological history

Formed in shallow marine or terrestrial environments through the accumulation of organic debris, shell fragments, and bone or plant material that underwent mineral replacement (permineralization/petrifaction) over millions of years.

Uses & applications

Primarily collected as geological educational specimens, decorative display rocks, and fossils. In larger quantities, limestone is used in construction and cement production.

Geological facts

Fossilized organic materials retain fine structural details because silica, calcite, or iron minerals replace the original biological tissues cell by cell.

Field identification & locations

Identified in the field by its distinct organic texture, fine grain, and typical reaction to dilute hydrochloric acid (if calcitic). Commonly found in sedimentary basins and riverbeds known for fossil deposits.