I dont think the dishwasher would hurt your stone a bit if you dont use the heating element to dry it, let it air dry, it gets VERY HOT in a dishwasher,and if any water is trapped within the stone and tries to expand as it heats up,CRACK! The only other negative I can forsee is that as time goes buy the metal particulate could eat at the plastic pump, but that would take years and youd never know it.