fossil

Fossil Assortment and Geological Specimens

Various (including Ammonoidea)

Hardness varies by specimen (typically 3-5 on Mohs scale for fossiliferous limestone and calcite replacements); colors range from gray, brown, and tan to dark basaltic black; lusters are generally dull to earthy.

Identified August 3, 2026More fossil →

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Physical properties

Formation & geological history

Formed through sedimentary processes, fossilization, and volcanic activity over millions of years, with marine fossils originating from ancient shallow seas.

Uses & applications

Used for educational purposes, paleontological study, decorative display, and as collector specimens.

Geological facts

The box contains a visible ammonite fossil at the top left, which is an extinct cephalopod mollusk closely related to modern squids and octopuses.

Field identification & locations

Key identifier is the distinct coiled spiral shape of the ammonite and the presence of fossil impressions in sedimentary matrix. Found worldwide in sedimentary rock layers.

Other fossil specimens

See all

Crinoid Stem Fossil in Matrix

Phylum Echinodermata, Class Crinoidea

fossil

Sedimentary Outcrop (Sandstone/Shale)

Sedimentary bedrock formation (variable composition)

sedimentary

Chert with Fossil Brachiopod

Microcrystalline Quartz (SiO2) with Calcitic Brachiopod inclusion

sedimentary

Crinoid Stem Fossils (Indian Beads / St. Cuthbert's Beads)

Crinoid columnal ossicles (phylum Echinodermata)

fossil

Fossilized Crinoid Stem in Limestone

Crinoidea (Class) in Calcium Carbonate (CaCO3) matrix

fossil

Fossiliferous Limestone

Limestone with embedded fossil cross-section

sedimentary