Cosmic spherules, asteroidal collisions and the possibility

dated deep-sea cores, should provide a test of whether or not cosmic spherules originate in asteroidal collisions. If D is the overall diameter of the spherule and 6 its bulk density, the effect predicts that a number of straight sloping lines should appear in a plot of D6 against arrival time for spherules down a core. From a Pacific core, 223 iron spherules (Dz45pm), in a variety of states, were examined to estimate 6. But, a decision was made to use only 100 spherules in a final D6 plot as 6 had dubious accuracy for spherules with rusted or missing metal globules and for those with enclosed or burst bubbles. In this plot, two parallel sloping lines appear with some clarity. They are widely spaced in time and could be due to infrequent collisions amongst the few asteroids at- 3.4 AU. Possibly, there are more frequent collisions in the main belts, but lines showing these are not clearly revealed. During the examination (i.e. by cracking the spherules), 16 iron spherules of a new type were found. Instead of a metal globule, a black bead of glass is eccentrically enclosed in the oxide shell. The bead is a true non-magneti