According to the tag, this was found in Southwest Virginia. Does anybody have any idea what it may have been used for? The iron plate measures about 12 1/2" x 1 3/4". Overall, this is about 20" x 3". The sizes of the holes are graduated. Thanks for your help!
Loom does sound reasonable, though I've never inspected one up-close.
Another possibility is a device to plant rows of seeds, but I would question the overall length (seems like it should be longer)?
Thank you everyone for all your help. I actually have an answer from outside the group. It appears this is some kind of mold for making lead shot or round balls. I'm told it is probably late 18th century or early 19th century.