Dough-Joe&reg; Pizza and Baking Stone MADE IN USA--These are the improved version of our original stones; These are dense, thick cordierite and are far more heat shock resistant. Their thickness allows them to contain a huge amount of heat FOUR-PIECE set of 6x9-inch tiles allows the flexibility of cooking small items like bread or a large pizza. ACTUAL WEIGHT OF 4 IS ABOUT 12 POUNDS. We jimmied with the "Official" shipping weight to get the Amazon shipping template to work with all our products. Because of the way they release from the dies in the press, the stone may have tiny chips along the edges. Multiple stones are less prone to oven stress breakage than one large stone. They actually do not move around much unless you really strike them hard. DO NOT SEASON. Works perfectly on the grill and small grills benefit with the ability to mix the stones around