I just recently bought a new-to-me show halter and I cleaned it all up just like I do my other tack. It's silver plate, and came out mostly clean. However, there are some parts of the silver that are supposed to be white, and they are most definitely not. They are a stained yellow color. I used toothpaste, and then put a vinegar/baking soda paste on. I normally use this mix, or my jewelry cleaner or NevrDull. I've never had this issue with my other tack with the same type of "white" design. Anyone have any good cleaning ideas for this??? I can try to get pictures tomorrow of the dingy spotted halter and comparison pictures of my headstall. Thank you!