My knowledge of tools is limited, but I believe this would have been used by a blacksmith doing fine work, or a jeweler, and I guess the pair of wonderfully snake-like recessed forms at the top represent hooks or perhaps clasps that would have been forged on it. Lettering was pressed into the sides in the form of two "X"'s--a bit hard to read, but I can make out something along the lines of Dasteel. I find it just a very satisfying and sculptural thing, and the iron is gorgeous. And weighing almost 4 pounds, a very good paper weight or door stop, too. The person I purchased this from dated it to c. 1850. 

3 1/4 x 2 3/4 x 2 9/16 and in excellent condition.