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Message:: [QUOTE="Curtis, post: 944117, member: 26430"]I have a few coins with bronze disease, which I’ve been managing by periodic baking or sunning, and generally storing in a very dry, closed trunk with open containers of desiccant to keep them ultra-dry (plus the de-humidifier machine that runs 24/7 in the corner of the room, but that’s an expensive option for not too much return). So the BD hasn't really advanced much, even though I have moved from arid Arizona to humid Illinois. I’m considering testing Sodium Tetraborate, aka, Borax, to see if that works. I am hoping I may get some input here on that. My main concern is that my BD coins tend to actually be the better ones... or maybe I just notice it on better ones, since the worse ones pile up in boxes and bags of hundreds and up (I'm talking culls from bulk uncleaned lots here, and it's hard to find any clear BD cases--I guess it's the ones that get the most attention, having been soaked or treated with acidic solutions, that end up with the BD). Usually people talk about treating bronze disease with sodium bicarbonate (baking soda) + sodium carbonate (“washing soda”)—the latter I guess can be hard to find except online, and there it is expensive. Also there are the Gringott’s BD Killer type products—don’t know what the ingredients are in those. Another I’ve seen mentioned in more scholarly/expert publications (beyond my level of understanding) is Sodium Sesquicarbonate, which supposedly works very well without being overly destructive of patina—but this is even harder to find, except in chemical supply stores. All these things are alkaline/basic, like lye, which is important because acids reacting with the bronze, in the presence of moisture, are the culprits, as I understand it. Besides the commercial solutions, all those have similar uses: water softening, desiccants, detergents/soap bases (instead of lye), jewelry/metallurgy uses. (Someone mentioned something called biox in an older thread, and I couldn’t find any information about that...) One product that I’ve not heard mentioned is Borax (Sodium Tetraborate). This is widely available and cheap. It has the same household uses and similar alkalinity to S Carb and S Sesquicarb. My hunch—based on very minimal understanding of chemistry—is that Borax would work (i.e., dissolved in boiling water, á la baking +washing sodas method). They are salts of different acids: carbonic vs boric acids. I’m not sure what that means exactly, except that Borax isn’t as similar to sodium carbonate as sodium sesquicarbonate is (both widely purported remedies). Would anyone provide an opinion, based on experience or chemistry expertise, on whether S Tetraborate would work? I am considering trying it on some cull coins (which don’t happen to have BD) for practice, mainly to see what it does to different kinds of patina at different concentrations. Even if it turns out non-destructive, though, I’d feel better about stepping up to the few BD coins. Maybe I could “give” some of my culls BD by letting them sit in the bottom of the cat litter box for a month or so... :goofer:[/QUOTE]

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