It's dead skin cells or tiny feather bits that shed off the bird. It's white just like human dandruff. All birds do this, just some are worse than others. Make sure your bird can bathe itself every day if it wants to and that might help. Some people are allergic to the dander, so keep the cage clean.
African dry skin,,,,you need to get a spray bottle spray your bird 2 x a day,, but now what i would do is buy a conditioner at a pet store and spray your bird with that until its all gone it has an oil to keep your birds skin moist,,,,,,easy fix....good luck
Is it those littile white balls of feather?I'm confused.