Dust consists mostly of abraded fragments form larger objects. The things that turn into dust can be almost anything from cabbages (fragments of dried vegetable matter) to kings (especially if cremated). Dust is so powerful that the wind driven ones have cut fantastic shapes on the canyons and badlands of America over millions of years. There are no borders for dust and can appear any where.
The reason why dust keeps reappearing is that the dust cloth used for dusting simply stirs up the dust temporarily and the fall back and fresh dust keeps coming in all of the time.
