fossil

Belemnite Fossil

Belemnitida (rostrum)

Hardness of 3.5 to 4 on the Mohs scale, typically brown or yellowish-white, bullet or cigar-shaped, made of fibrous calcite.

Identified October 24, 2026More fossil →

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Physical properties

Hardness of 3.5 to 4 on the Mohs scale, typically brown or yellowish-white, bullet or cigar-shaped, made of fibrous calcite.

Formed during the Mesozoic era from the calcified internal guards (rostra) of ancient squid-like cephalopods.

Valued by fossil collectors and used in biostratigraphy to date marine sedimentary rock layers.

Commonly known as 'thunderbolts' in folklore, ancient people believed they fell from the sky during lightning storms.

Easily identified by its distinctive bullet-like symmetry and fibrous calcite cross-section, commonly found in marine limestone and chalk deposits.

Probable fossil-bearing rock or mineral concretion

Unidentified carbonate-rich concretion with a possible fossil inclusion

Likely fossil oyster shell

Fossilized bivalve shell; exact species cannot be identified from the image

Crinoid Stem Fossil in Matrix

Phylum Echinodermata, Class Crinoidea

Fossiliferous limestone (likely a crinoidal or shell-fragment limestone)

Bioclastic limestone, composed chiefly of calcite (CaCO₃)

Porous limestone pebble

Calcite-rich limestone (primarily CaCO₃); exact identification is uncertain from the image

Weathered fossil bone fragment (identification uncertain)

Fossilized bone; exact taxon and mineral composition cannot be determined from the image