All of my Pet Treat Jars are made b me on my wheel and fired in my Oxidation Kiln to over 2,200 degrees. These Stoneware Jars are Food, Dishwasher and Microwave Safe and are glazed on the inside as well as the outside. I love making covered "Pots" and especially love making Treats Jars for my Best Friend. I hope you love them too.