*Tips on microwaving hand thrown stoneware pottery:
I throw in both white and brown stoneware. It is said that if the clay is white, it is microwave safe. Red and brown clays contains iron, as do red and brown glazes. As we know, metal in the microwave is not good. However, I personally have gotten years, so far, out of my brown stoneware pieces, including microwaving them.
For microwaving on pottery, you will reduce the chance of breakage if you place the food evenly on the inside of the container. Microwaved or oven warmed pieces will be hot when you remove them. Never stack empty pottery to warm them in the microwave or the oven.