less than 30 mesh may however be preferred for some such applications depending on cost rubber particles having particle sizes of less than 80 mesh or less than 140 mesh may prove suitable in some applications recycled rubber particles of these sizes are available for example from simply pulverizing discarded rubber products such as worn tires tennis balls and other rubber containing materials for more specialist applications particles of a smaller particle size below say 200 u s mesh preferably 300 u s mesh or finer are preferred particles of these fine particle sizes are obtainable for example by freezing recycled tires and other rubber products and then pulverizing them for some applications a mixture of particles of different sizes may be appropriate for example i have found that for highway and parking lot use a mixture of particles of 10 20 mesh with those having a particle size of less than 30 or 40 mesh may be desirable recycled rubber of the coarser particle sizes employed in the present invention is widely available from a variety of sources the finer sized particles are available for example as polydyne 80 and polydyne 140 from lehigh technologies of tucker ga glass or plastic particles for use in the compositions of the present invention are typically of a particle size of less than 100 u s mesh 149 microns more preferably from 3 to 50 microns such glass particles may be solid or hollow conveniently some or all of the particles may be obtained from crushed recycled glass or waste fiberglass i have found that solid glass spheres of a mean particle size of 1 to 50 microns more preferably 5 to 20 microns are useful in the compositions of the invention in.