Chandana Witharanage posted a photo:

Macro Mondays - Textures
Less than 3"

Small section of a Vintage Fossilized Brain Coral

This is a natural white brain coral skeleton often used for nautical or coastal home decor. It is composed of a hard calcium carbonate skeleton secreted by marine polyps. These specimens are frequently found washed ashore on beaches or sourced from shallow tropical reefs. You might consider using it as a decorative element in a book case or display cabinet.

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