The difference, now a days, between a solid and a pearl are minuscule....and if one does not concur, take 2 balls of the exact same type that come in a solid and a pearl...lay em out the same and knock the surfaces down to 360-500 then smooth up to whatever desired surface, then throw...the same amount of times. Unless the density of the materials used changes, i.e. pearl additive...the reaction does not change. Case in point, all solids tend to have surface and pearls are shiny....what dictates reaction?