Bu stearate, glycerol triacetate and trioleate, liq. and chlorinated paraffins, CCI4, tetrachloroethane, Et3SiO4, Bu3PO4 and Me3BO3 were added (3% by mass) to the liq. paraffin and an emulsifier-contg. (7% and 0.5% by mass, resp.) aq. grinding fluid used for machining Si3N4 plates with a diamond abrasive wheel. The addn. of chlorinated paraffin had no significant effect on grinding wheel blunting while the addn. of esters resulted in limiting phenomenon. The compds. with the C chain length near to 18 and similar polarity to the ceramics showed the best anti-clogging ability. Use of a mixt. of Si, P and/or B-contg. short-chain esters gave not always an advantageous synergic effect.