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One of the reasons I love vintage brass so much is that it often looks lovely with the patina and wear of time, but if there are particularly nasty blemishes you can also clean it up and make it look almost good as new. The vintage decor items I carry in the Valerie Tyler Collection are a combination of pieces that I have left the original patina on, as well as others I felt would look nice with a little shine. Sometimes I even find pieces in which the owners kept the items shiny and polished for years!
Typically when I want to polish up a piece I use a product called Twinkle
It's an easy to use polish. I just run my item under rather hot water, spread the paste on with a provided sponge and within seconds it starts to get lighter and shinier. I have found it doesn't work on really tough spots, so at times I will use a toothbrush or even extremely fine sandpaper to clean off particularly troublesome areas.
A little trick I learned from being a jewelry designer is that you can buy abrasive paper in extremely fine grit. Use it carefully on brass items and it can really add a shine. (3M WET/DRY polishing paper
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If you want to avoid commercial brass cleaners, a few alternatives that sometimes work include ketchup (leave on for 10-15 minutes then rinse) and yogurt (allow it to dry then wash off)
A note of caution, an item that may appear brass may actually be merely plated and something altogether different under the plating. You can determine if it's plated a few ways. If a magnet sticks to the item there is most likely steel or iron beneath the plating. You can also use a nail or small sharp object to put a small scratch in the item in a hidden spot. Anything other than a bright gold color and you probably have something that is not solid brass.
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