fossil

Polished fossil coral (likely agatized coral)

Fossilized colonial coral; commonly silicified as chalcedony/quartz (SiO₂)

AI-generated identification · may be incorrect

Rounded, highly polished brown-and-cream specimen with faint tightly packed corallite/pore patterns. Likely hardness about 6.5–7, vitreous to waxy luster, cryptocrystalline quartz, no obvious cleavage; specific gravity roughly 2.5–2.7.

Identified September 14, 2026More fossil →

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Physical properties

Formation & geological history

Ancient coral reefs were buried, then their carbonate skeletons were replaced or infilled by silica-rich groundwater. The precise geological age cannot be determined visually; likely Paleozoic–Cenozoic depending on source.

Uses & applications

Used as a lapidary ornamental stone, cabochon, carving, paperweight, or collector fossil. It is not suitable for structural construction.

Geological facts

The circular or honeycomb-like markings distinguish coral from ordinary jasper, though polishing can obscure them. Brown coloration may reflect iron oxides or other impurities.

Field identification & locations

Look for repeated tiny corallite cups or radiating septa under magnification; a vinegar reaction may occur only where unaltered calcite remains. Trinidad’s region includes sedimentary rocks and fossil-bearing marine deposits, making fossil coral/jasper plausible, though the image alone cannot establish provenance.