What is this close-up picture? (WotsThat: Coral skeleton (macro))

Question

What object is shown in this zoomed-in close-up photo?

FeldsparGhost · Accepted Answer

Coral skeleton (macro). Coral skeletons are actually the architectural masterpieces of tiny polyp colonies, with each skeleton telling a story of symbiosis between coral and algae. Under magnification, you can see the intricate calcium carbonate structures that support these ancient creatures, some of which have been building reefs for millions of years.

Answer: Coral skeleton (macro)

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