Sr. Jose,
From the pictures and your description, I am guessing that the gun was restored at some point. The yellow is old varnish. You can take it off easily with some denatured alcohol.
Follow Rockdoc's advice and take off the barrels. Turn the barrels over and look near the lug for any proof marks. Also, check the receiver, where the barrels lock down. If there are any marks, take a picture and post it here. Some one should be able to make some sense out of them. The name alone is intriguing.
Pete
