This large mug with sturdy thumb grip has a surface reminiscent of a deeply rich forest or jungle. The outside slip is made from quarry stone mined locally andcombines with salt vapors to produce the surface color. A full 25 ounces allows plenty of your preferred beverage. I dig my clay, allow to dry then run thru a hammer mill. Add a locally mined kaolin. A small amount of lower firing clay or feldspar helps keep porosity close to 5 to 6%. I mix clay in the spring. Food safe, can microwave, oven proof. Large Salt Glazed Pottery Mug 25 Oz. Combed Quarry Stone Glaze