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In a glass of milk, nothing is white

And yet it is

White is made by light

It's packed with billions of beads of fat and protein, floating in water

Light goes in, bounces from bead to bead, and leaves, returning every colour in equal measure

Your brain reads that as white

Skimmed, it drifts toward blue

Butter goes yellow, from a pigment in the grass

And sheep's milk is even whiter

That white is not a shade: it is light lost along the way