If you remove the overflow cover, the material between it and the plumbing will be about 1/4 " thick if it is cast iron. 1/16" if it is steel. Or you can push against the skirt. If it flexes at all, it is steel... if it is solid, very likely cast. Cast iron does not rust as often as steel, but that is not to say that you will not get rust spots from a cast iron tub. Most steel tubs would have the same feel that kicking an older car might be imagined to be, where as cast iron would feel much more solid, like kicking a large rock.. If you want, remove the overflow cover and popup lever from the head end of the tub and look at the edge of the hole. ?)
:laughing: If you can pick it up by yourself at all its not cast iron. :laughing:The guys have it pretty well covered except If you can pick it up without giving yourself a hernia it is not cast iron.