Peaaegu täiuslikud kerajad osakesed on haruldased, kuna tegelikult on palju võimalikke hälbeid sfäärist, kuid enamik neist siiski mahuvad selle termini rakendusalasse.
Near perfect spherical particles are rare. In reality there are many possible deviations from a sphere that nonetheless are accommodated by most applications of this term in particle technology.
