Le Creuset Stoneware French Onion Soup (set of 2), Citrus Virtually non-porous stoneware is fired at 2160 degree's, giving it unmatched strength and durability and making it resistant to chipping, cracking and staining. Won't absorb odors or flavors and resists moisture absorption. Enameled surface makes it easy to clean and scratch resistant. Oven, microwave, refrigerator, freezer safe