What is this close-up picture? (WotsThat: Sandpaper grit (macro))

Question

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

OceanWatcher · Accepted Answer

Sandpaper grit (macro). The grit numbers on sandpaper don't actually measure individual particle size—they measure how many particles fit through a standard sieve, which means a "220 grit" sandpaper might have particles ranging wildly in size, creating a surprisingly inconsistent surface. This is why premium sandpaper brands use additional screening steps to sort particles by actual size, resulting in smoother, more predictable finishes that cheaper alternatives can't match.

Answer: Sandpaper grit (macro)

More industrial close-ups