Tinned metal, which is well tempered, also, gives a thin, brown crust to layer cakes and pies. It makes good bread, loaf cake and cooky pans. Most of the cheap tin of today is iron-coated with very little tin. It does good work, but utensils made of it cannot be kept as well polished and as attractive in appearance as more heavily-tinned ones. Sheet iron, heavy steel and cast iron make the most popular frying pans. The heavy iron, holding heat as it does, makes a desirable brown coating on most foods without the danger of burning experienced with frying pans of other materials. This is due to specific heat and conductivity of the metal. Sheet-iron frying pans are useful in cooking foods which are wanted on short notice. The small-sized ones are most in use. =193. Aluminum Alloy.= Satisfactory frying pans are made from aluminum alloyed with other metal and cast. Real aluminum frying pans warp. They do not brown the food as well as materials that conduct heat less rapidly. =194. Cast-Iron Utensils.= Heavy cast iron finds special favor in the making of pot roasts, bread sticks and popovers. It browns the roast and makes a thick crust on bread sticks and popovers. All iron or tin utensils give better service as they become tempered with use. They must be kept dry in order to prevent rust. Do not use them for cooking acid foods. Granite, cast aluminum and Russia iron are the popular and satisfactory materials for roasting pans. =195. Earthenware.= For casseroles and bean pots, earthenware is a favorite material, the heavy glass gives equally good results. These materials are fitted for long, slow baking of food. They hold heat and conduct it to the food in such a way as to produce results which are difficult to duplicate with utensils of other materials. =196. Aluminum and Graniteware.= Stew pans are proving satisfactory when made of aluminum and of high-grade graniteware. An assortment of pans and double boilers containing utensils of each material gives the best results, as the granite is most desirable for cooking some acid and very salty food, while aluminum is light and satisfactory for preparing other dishes. Never let food stand in aluminum or granite dishes after being cooked. High-grade graniteware is not as readily affected by acids as the low, cheap grade. Enameled ware, which is roughened by a dilute solution of vinegar, is likely to contain substances injurious to health. Ink will not stain good enameled ware. Graniteware, like glass and earthenware, makes a heavy crust on the dishes being baked in them. Graniteware is metal, coated with a sort of glass. It must be treated like glass. It cracks when dropped. Never set it on a hot stove when empty or cold, as the heat of the stove will crack it as it will glass. When hot, do not set it on a cold marble or a metal table top, as sudden changes in temperature will crack it. With proper care, granite and enameled ware give good service.