fossil

Fossil Shell

Invertebrate fossil (Mollusca)

Hardness: 3.5 to 4 (if replaced by calcite), Color: Cream, white, and grayish tones, Luster: Vitreous to dull, Crystal structure: Trigonal (calcite replacement)

Hardness: 3

Identified July 31, 2026More fossil →

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Physical properties

Hardness: 3.5 to 4 (if replaced by calcite), Color: Cream, white, and grayish tones, Luster: Vitreous to dull, Crystal structure: Trigonal (calcite replacement)

Formation & geological history

Formed through the process of permineralization or replacement where the original shell material of marine organisms is slowly substituted by minerals like calcite, silica, or pyrite over millions of years.

Uses & applications

Used for educational purposes, paleontological research, decorative display pieces, and by fossil collectors.

Geological facts

Fossilized shells provide crucial evidence of ancient marine ecosystems, past climates, and the evolutionary history of invertebrates dating back hundreds of millions of years.

Field identification & locations

Found in sedimentary rock layers worldwide, particularly in ancient marine deposits, limestone formations, and coastal cliffs. Identify by distinctive spiral or bivalve shell shapes preserved in stone.