Hi Janis,
Yes, Griswold made a line called Iron Mountain. You can spot them by the distinct handle style, and they will also have a four digit number cast into the bottom. They are every bit as good to cook in as a marked Griswold, the quality of casting and finish is equal.
It is thought that these were sold at a lower price, to compete with other foundries, without having to lower the price of marked Griswold cookware. Originally, they would have had a paper label.
Chris