I believe "latten brass" is more tarnish resistant. A very yellow metal. Used for decorative brassware and famous as the copper alloy for medieval church monumental brasses. This would also has been used in Africa and Asia and still used today. I have African brass weapons on disply in the hallway open to all the kitchen steam and so on, been there well over a decade, still clean. I favour a mediterranean origin. Clearly an old piece but I do not think older than a century or two. I know little really though.
P.S. possibly similar to "naval brass" the fact that lead is not used in the alloy help resist corrosion and tarnish.
P.P.S these brasses will tarnish if buried or exposed to extremes but if kept in "normal" conditions and frequently handled they will stay tranish free. Brasses like all the
GOLD kofkari and inlay we see. These people are on to it.
http://www.rings-things.com/press/an...ish_brass.html
P.P.P.S --scroll down to brasses for decorative applications.
http://www.copperinfo.co.uk/alloys/b...ight-brass.pdf