When you swim into shore, this is what you are really stepping on: Grains of sand photo-magnified 250-times their size!

From the Mail Online:

Viewed at a magnification of over 250 times real life, tiny grains of sand are shown to be delicate, colourful structures as unique as snowflakes.
When seen well beyond the limits of human eyesight, the miniature particles are exposed as fragments of crystals, spiral fragments of shells and crumbs of volcanic rock.

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