What is this close-up picture? (WotsThat: Shingle beach stones texture (macro))

Question

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

GarnetSweep · Accepted Answer

Shingle beach stones texture (macro). A shingle beach forms where waves are strong enough to wash away fine sand but not powerful enough to move larger stones, sorting the beach material by size as the water rakes it back and forth.

Answer: Shingle beach stones texture (macro)

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