WHAT! You're having a party and I wasn't invited???
Nothing seems to get the passions going better than to bling or not to bling. I don't really care one way or the other. I reloaded without a tumbler or bling for 30 years. Always wanted a tumbler, but never got around to it. Now that I have a big ole Lyman 2500, I admit it, I like being vain. What's not to like! But mostly I like not have to rub my brass down one at a time to clean it preparatory to sizing. I use 20/40 cob and a capful of Dillon brass polish, and it makes it plenty purty. (I use Dillon just because they stock the stuff close by...I just pour it over my filled-up tumbler full of cob and brass, and I've never seen a single clump last more than a couple of minutes of tumbling.)
But all that is irrelevent to the original question. Mine doesn't stay blingy if I'm wanting to store it for a rainy day. So what? Well the O.P. cares. So here's a way to make it last for a long long time if that's what's important to you:
Acid neutral, water and alcohol resistant.
Preferred by museums worldwide for protecting furniture, leather, marble, paintings and
metal.
Will not stain or discolor with aging. You use the tiniest amount. No more than a molecule or two between your brass and the chamber...unmeasurable by anything I own. One 200ml container will last a lifetime.
Do I make it? Heavens no, it was created in England for the National Museum. But you can get it in the States,
HERE. When I have to restore something, I protect it with this. BTW, the site has a video on it.