fossil

Fossiliferous limestone with brachiopod or bryozoan fossils

Calcite (CaCO₃) limestone containing marine invertebrate fossils, possibly brachiopoda or bryozoa

AI-generated identification · may be incorrect

Gray-brown, fine-grained carbonate rock with raised fossil molds and delicate netlike/linear structures; calcite has Mohs hardness 3, vitreous to dull luster, rhombohedral cleavage, and commonly effervesces in dilute hydrochloric acid.

Identified August 13, 2026More fossil →

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At a glance

Common name: Fossiliferous limestone with brachiopod or bryozoan fossils
Scientific name: Calcite (CaCO₃) limestone containing marine invertebrate fossils, possibly brachiopoda or bryozoa
Category: fossil
Identified: August 13, 2026
Method: Standard

AI Estimated Value

About $5–$30 for a common hand specimen; $30–$150+ if the fossils are exceptionally clear, complete, or locality-documented.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Formed when marine shells and skeletal debris accumulated, were compacted, and cemented in shallow seas, likely during the Paleozoic or Mesozoic Era; the exact age requires locality and laboratory study.

Uses & applications

Used as a teaching and collecting specimen; limestone is also quarried for cement, aggregate, building stone, and agricultural lime, while intact fossils have modest display value.

Geological facts

The visible patterned structures may represent brachiopod shell ornamentation, bryozoan colonies, or crinoid debris; weathering preferentially exposes fossil surfaces and casts.

Field identification & locations

Look for acid fizz, abundant calcite, and repeated biological patterns rather than crystal grains; common in ancient marine sedimentary formations worldwide, especially North America and Europe.