fossil

Fossilized coral with attached shell

Likely fossil coral (Scleractinia or Tabulata), with a bivalve or gastropod shell; exact identification requires microscopy

AI-generated identification · may be incorrect

Hardness about 3–4 for calcitic material; tan to brown, porous, and dull to weakly crystalline. The cavities are coral corallites or weathered bioerosion holes, while the smooth lower structure appears shell material, probably aragonite or calcite.

Identified September 10, 2026More fossil →

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At a glance

Common name: Fossilized coral with attached shell
Scientific name: Likely fossil coral (Scleractinia or Tabulata), with a bivalve or gastropod shell; exact identification requires microscopy
Category: fossil
Identified: September 10, 2026
Method: Standard

AI Estimated Value

About $10–$60 for a common loose specimen; $75–$200+ if locality, preservation, and fossil identification are 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

A marine carbonate fossil formed when colonial coral and mollusk shells were buried and mineralized, commonly during the Paleozoic–Cenozoic. Groundwater may have replaced original aragonite with calcite and partially weathered the specimen.

Uses & applications

Primarily a collector’s specimen, teaching aid, or decorative natural-history object; not generally suitable for construction or jewelry. Avoid acids and prolonged water exposure, which can etch carbonate material.

Geological facts

The honeycomb-like pores may represent individual coral animal chambers, but some openings could be later boring traces made by marine organisms. The attached smooth shell makes this a composite fossil rather than a single mineral crystal.

Field identification & locations

Look for repeated polygonal corallites, septa, growth patterns, and recognizable shell margins; dilute hydrochloric acid or vinegar may fizz, though testing can damage it. Fossil corals occur widely in ancient marine limestones worldwide.