1904 Lionel Train Set

Well, I'd love to give you an appraisal here, but your details are a little vague. There are an awful lot of "cast iron Lionels" out there, some of which are rare and valuable and some of which are not.

What I need to know is this:
--What is the distance between the (outside) rails?
--How is it powered? Clockwork, battery, electricity, none at all?
--What kind of locomotive is there? Steam engine, diesel, boxcab-thingy (electric)? What color is it?
--What kinds of cars are there? Gondolas, flat cars, boxcars, cabooses, coaches? What colors are they?
--Are there any numbers or markings written on the cars and engine? (This is important, since us collectors identify the trains by their numbers!)

Sight unseen, I'll offer a few speculations. If this train set you talk about truly IS a Lionel from 1904, it is very rare and valuable. But Lionel did not make many cast-iron trains; most of theirs were stamped steel. There was a company called Ives that made cast-iron clockwork trains in the very early 1900's. Those are desirable, but not quite like early Lionels are. An early Ives is worth several hundred dollars, but an early Lionel is worth thousands.