KellyLV, I have had the same tarnish on the gold extender I use for my black MC pochette accessoires.. However, it only happened while I was on vacation in Indonesia where it's super humid (like 98% humidity or so)...I freaked out over there, but when I got back to Germany, where the climate is extremely dry, the spots disappeared by themselves without any treatment! Maybe your area is humid too...? Try a brass polish with a microfibre towel and polish it lightly....I did that with my brand new Mini Lin lock which had slight tarnishing the day I purchased it, and almost all the tarnish went away...good luck!