Q: This picture is of the mark on a pottery "pig" we found. It has several places without the glaze. Can you give us any information about its origin and value? A: You used an unfamiliar but correct name for your antique. Foot warmers are sometimes called "pigs." The proof is in the words "For Cold Feet" on the top of your stoneware jug. It's a foot warmer, which was used to keep a person's feet warm in the cold weather. In the days before homes with central heat and cars with heaters, they were necessary. Foot warmers were made of pottery, tin, or soapstone and held charcoal or hot water. Yours would have been filled with hot water. The warmer was put under a person's feet and then their legs and feet were covered with a blanket to keep in the heat. Your foot warmer was made by the Adirondack Hardware Company in Saranac Lake, New York. The damage hides the words "Ad-Har-Co., Trade Mark, Stone Pigs." Stoneware foot warmers like yours usually sell for $50 to $100, but because yours is damaged it is worth about half.