All the pottery I make is Stoneware. This means it is al fired at 1250 C. The high temperature makes the clay body sinter togheter with the glaze. This makes it non porous, unlike earthenware wich is porous and the glaze is not realy baked on the body wich causes it to chip easily.
All pieces are safe to use in the microwave and dishwasher. My advise is however to wash it manualy because my experience is that breakage occures while loading and unloading the dishwasher.