Hi all -- I like to buy old cast iron pieces at yard sales & flea markets. Some of them are terribly rusty and gunky. (I prefer old Griswold cast iron items.) I found the best way to clean them very thoroughly is to spray them with oven cleaner and seal them in a plastic trash can bag overnight. Wash them down good the next morning. (I saw this on a TV show.) I put a little vinegar in the final rinse to be sure all the oven cleaner is neutralized. Then I give them the oil treatment and put them in a very low oven for an hour or two. Then I buff them really good with a soft old towel to remove excess oil. This oil/oven treatment is called "seasoning." I prefer to season with mineral oil. And is perfectly safe for human consumption. You can buy mineral oil in drug stores or the pharmacy section of grocery stores. When I use my seasoned pans, I am careful to not use harsh cleaning that removes the seasoning. But once in a while, after washing them, I rub the inside with a little vegetable oil and stick in a low oven for a few minutes -- just as a precaution against possible rusting. I use vegetable oil for this only because it is so handy. More on mineral oil -- Wooden cutting boards -- when I clean my wooden cutting boards and chopping block, I treat them with mineral oil. No oven, of course. I just rub on a heavy coat of mineral oil and let it set for an hour or so -- then wipe off excess. Works great. You never get that rancid odor that vegetable oils sometimes develop after a while. And the wood is never "sticky." And, if any of you collect old metal items, mineral oil works great on them too. I collect old tools and flat irons. These have both metal and wood. After I clean them thoroughly, I give them the mineral oil treatment (without the oven) and they look great. Phyllis in NJ