Colt cylinder pins gathering rust.
I noticed no matter how you clean an 1851 or 1861 Navy etc. rust forms on the greased cylinder pin. I used to use thompson's Blue lube(Comes in a brown tube) but I havent in awhile. . But I liked it. I guess I should have tried it before posting but haven't shot guns lately except a 61 navy. I thought it was cleaner than a whistle.I took a tube of CVA and it does not work but just makes brown greasy rust.