What is this close-up picture? (WotsThat: Fish scales (macro))

Question

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

ThornPetal · Accepted Answer

Fish scales (macro). Fish scales are covered in a protective layer of slime that's so effective at reducing drag that engineers have studied it to design faster swimsuits and ship hulls. Even more wild: some fish scales are so reflective and precisely structured that they can create colors without any pigment at all, using the same light-bending trick that makes oil slicks shimmer.

Answer: Fish scales (macro)

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