As part of an ongoing study to determine how the wear of mining tools affects dust generation, the Bureau of Mines has measured bit temperature rise during cutting of abrasive rock. Radial bit wear- flat temperatures generated by linear cutting in Berea sandstone were measured as a function of cutting depth and speed. Depths of cut (doc) were 1/8, 1/4, and 1/2 in, and cutting speeds were 10, 40, and 80 in/s, respectively. Temperature sensing was accomplished by emplacement of a miniature thermocouple into the center of the wear flat. Temperatures observed ranged from 200 degrees to 500 degrees c. Correlation between depth and temperature was weak. Temperature increased linearly with speed at 1/2-inch doc, but data taken at 1/8- and 1/4-in doc produced inconclusive results. The results indicated that, at least for deeper cuts (1/2 in), bit temperature, and therefore wear, can be reduced by lowering the cutting speed.