amp 0 6 8 42 214 0 02 0 15ca oh sub 2 10 90 clay amp 0 5 6 71 171 0 01 0 05cement 10 80 20 clay amp 0 5 6 55 167 0 04 0 02cement 10 90 10 prior artformalde 0 3 6 09 156 0 03 0 1hydeformalde 0 6 6 53 166 0 08 0 11hydeformalde 0 25 6 37 162 0 02 0 02hydeformalde 0 3 4 18 106 0 02 0 03hydeformalde 0 6 6 54 166 0 02 0 06hydeurea form 0 3 5 42 138 0 02 0 03aldehydeurea form aldehyde 0 3 5 57 142 0 06 0 17urea form 0 6 6 89 175 0 1 0 05aldehydecontrolurea prills 2 26 57urea gran 3 78 0 58 0 67urea gran 3 58 0 04 0 19urea gran 4 32 0 02 0 04urea gran 4 05 0 08 0 58urea gran 3 93 100 average ______________________________________ from the data in table 1 it is apparent that the samples containing the finely divided inorganic materials in accordance with the present invention yielded crushing strengths abrasion resistance and impact resistance significantly better than those attained with untreated urea and equal to or greater than the results achieved with the urea particles to which formaldehyde had been added the results show that commercially produced granules manufactured in accordance with the present invention would have acceptable levels of strength abrasion and impact resistance commercially available urea granules usually contain at least 46 nitrogen urea is generally 46 44 nitrogen therefore in order to keep the nitrogen content above 46 percent the amount of additive and or impurities cannot exceed 0 95 the results in table 1.