An excellent recipe for cleaning brass

I bought a bunch of old post office lock box doors from a vendor in South Carolina and from an offer on eBay. They arrived in the same condition they were in when they were taken out of a post office being remodeled - dusty, dirty, and very tarnished. Along with the doors the South Carolina vendor sent a recipe for cleaning the brass - one portion of Coke to an equal portion of ammonia! I figured that this had to produce some kind of acidic liquid and took precautions: do the work outside, wear gloves, and prepare for really obnoxious fumes.
Well, most of my precautions were unnecessary. I could use my bare hands without any irritation and the fumes were certainly tolerable since I was outside. The impact on the brass was amazing. Although the directions said to let the doors soak for some time and to use a brass brush to clean the decorations, the brass brightened almost instantly and I used the brass brush sparingly. Dipping the doors in water after the Coke/ammonia soak produced an attractive door ready for my project. I applied a coat of spray lacquer as a finish.
I brought the recipe ingredients home to try on some brass house numbers that were so tarnished they were as brown as the painted wood post they were on. They took a little more scrubbing to get the brass to shine but the recipe worked much better than previous attempts.
I will be building some banks that use the post office box doors as a front door into the contents. I have also found a project to make large replicas of a post office truck where the post office box door is the back door of the truck. Right now I am gathering the cherry, walnut, and rosewood for those projects. More of this as the work starts.