fossil

Tumbled fossil coral or carbonate fossil fragment

Likely fossilized coral, composed mainly of calcite (CaCO₃); exact identification is uncertain from the image

AI-generated identification · may be incorrect

Cream to tan, matte-to-waxy surface with layered, cellular/ridged texture; calcite hardness ~3 Mohs, nonmetallic luster, and poor cleavage. It may fizz weakly with dilute hydrochloric acid, unlike many silicate rocks.

Identified August 13, 2026More fossil →

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At a glance

Common name: Tumbled fossil coral or carbonate fossil fragment
Scientific name: Likely fossilized coral, composed mainly of calcite (CaCO₃); exact identification is uncertain from the image
Category: fossil
Identified: August 13, 2026
Method: Standard

AI Estimated Value

Approximately $5–$25 for a small common tumbled specimen; $30–$100+ for larger, well-preserved, locality-labeled examples.

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

A marine skeletal fossil originally formed by coral colonies, later mineralized and lithified in limestone; age could range from Paleozoic to Cenozoic depending on provenance. The rounded edges indicate tumbling or polishing.

Uses & applications

Used as a low-cost fossil specimen, educational material, and decorative stone; not generally suitable for jewelry unless stabilized and polished.

Geological facts

The repeated internal ridges or compartments are consistent with biological structure rather than ordinary banding, but the photograph does not show enough detail for a confident genus-level identification.

Field identification & locations

Inspect a broken or magnified surface for regular corallite pores or septa; test cautiously with acid, and avoid prolonged soaking. Similar fossil coral occurs in limestone deposits worldwide, including Florida, Morocco, Indonesia, and parts of the Caribbean.