What is this close-up picture? (WotsThat: White pearl surface (macro))

Question

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

EchoVine · Accepted Answer

White pearl surface (macro). A pearl forms when an oyster or mollusc coats an irritant, like a grain of sand or a parasite, in layer after layer of nacre, the same iridescent material that lines the inside of its shell.

Answer: White pearl surface (macro)

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