Eagle and sword door knocker?

I am looking for info on what I think may be an old brass? eagle and sword door knocker? If it is a knocker, the knocker part is gone but there are holes where it once was? I am paricularly interested in design. An eagle on the top - a pretty rough design, and an arm holding a sword or scimitar? on the bottom half. The back is pretty corroded and there are no makers marks or designs or anything. It's an interesting item. It's about4 inches wide and 7 inches long. It's heavy too. I am pretty sure its brass though I am afraid to try to clean it as I have always been told to not clean really old items. If you have any info or ideas on this I would greatly appreciate it! Thanks!