Closed air circulation toner rounding

Toner is rounded by vigorously mixing less than about 5 percent by weight of particulate silica to the total weight of a starting toner in a closed, recirculating air system. The starting toner contains at least about 4.5 percent by weight of the starting toner of a wax and additionally contains at least 5 percent by weight of the starting toner of a softening agent. The temperature during the mixing is no more than 13 degrees C. above the onset of the glass transition temperature of the starting toner. The final toner comprises rounded starting toner having particulate silica embedded during the mixing process.