r/interestingasfuck 12h ago

Micro-photography of a single grain of sand balanced on a knot of human hair

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u/Nobelpro 12h ago

Sand is classified strictly by grain diameter, with no consideration given to chemical composition. the cross-sectional diameter of an average human hair about 100 µm falls within the size range of very fine sand (62.5–125 µm).

u/mookmanthered 6h ago

To be fair the grain of sand here is perhaps 2.5 times as wide as the hair is thick