Nanophase can make them 50 nanometers wide, which renders the zinc oxide transparent no more white goop since each crystalline particle is small enough to allow harmless light to pass through.

FORBES: The Science of Small

Nanophase can make them as small as 50 nanometers wide, which renders the zinc oxide transparent no more white goop since each crystalline particle is small enough to allow harmless light to pass through.

FORBES: The science of small