All functional ware is fired to stoneware temperatures of 1230-1240c. This means that the ceramics turn to stone and can therefore withstand oven temperatures and extreme cold.
Treat your functional ware as you would your current china ware. Don't boil dry, hold over direct heat or plunge from hot into cold water. I do however, place items in the dishwasher. I do not use the microwave as some glazes and clay bodies contain metallic oxides.