sedimentary

Weathered, porous limestone (likely fossiliferous or shell-rich)

Calcite-rich limestone, chiefly calcium carbonate (CaCO₃); exact identification is uncertain from the image alone.

AI-generated identification · may be incorrect

Beige-gray, rough and earthy, with visible pores and scattered darker grains or inclusions; likely Mohs hardness 3, with calcite’s vitreous-to-dull luster and trigonal crystal structure. A fresh surface may fizz when touched with dilute acid.

Identified October 7, 2026More sedimentary →

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At a glance

Common name: Weathered, porous limestone (likely fossiliferous or shell-rich)
Scientific name: Calcite-rich limestone, chiefly calcium carbonate (CaCO₃); exact identification is uncertain from the image alone.
Category: sedimentary
Identified: October 7, 2026
Method: Standard

AI Estimated Value

About $0–$5 for an ordinary hand-sized fragment; higher value would require a clearly diagnostic fossil or attractive specimen.

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

Likely formed from accumulated carbonate mud, shells, or other marine debris that compacted and lithified in a shallow-water setting; its geological age cannot be determined visually.

Uses & applications

Limestone is widely used for cement and lime production, crushed-stone aggregate, and building stone; this small weathered piece has little commercial value.

Geological facts

Limestone commonly dissolves in weak acids and can develop pores or cavities through weathering. The image does not show diagnostic fossils, so a shell-rich origin is only a possibility.

Field identification & locations

Look for a carbonate fizz, soft scratchability, and shell fragments or calcite grains on a broken face; common in sedimentary terrains worldwide. Avoid identifying its age or locality without more evidence.