Working hard to get my saddle clean. I use Lexol regularly and the leather looks great. However the brass plate (on seat back), and little Stubben symbols, and "D" rings (which are all gold/brass colored) have some tarnish and grime. What cleaner can I safely use on only those parts? I assume they are brass?? They are gold colored....and the tarnish is very green when I rub with paper towel. The tarnish is kind of down-in, between the brass and the leather of the saddle. It's a Stubben Camelot CC by the way.