Preventing Bronze Disease?

I appreciate your response. What you write makes a lot of sense. I'm left a little confused though because BadThad (I think that's his name, the chemist guy who created a great product I sometimes use, veridicare) wrote in another forum that BD is just a type of verdigris, like an advanced stage. I tend to believe that because the things I wrote previously about the soft metal seems like a form of BD/corrosion/veridigris. Sorry if I'm confusing things! In any case, I will probably carefully remove what I can on my coins, dry them appropriately, and then ren wax them. The next problem I have is airtight containers, which I read BadThad recommend. I sometimes use regular cardboard/mylar 2x2s. I live in CA so humidity is not a problem as far as I know. If anyone has a recommendation for holders, please let me know. I used the hard plastic 2x2s but in a lot of instances, the high relief part of coins easily cracked parts of the holders so that it obscures the coins and I end up putting them in cheap mylar 2x2s.

 

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How will you holder that? Will it just sit in a display case? I read somewhere that after baking and drying it, it's good to make sure it's in an airtight holder to prevent moisture re-starting BD

 

Sorry, but I can't give recommendations on any specific coins without seeing them. There are too many variables. Not all corrosion has to be removed.

In the past I have improved the appearance of a coin by removing corrosion, while other times I've made the coin look worse. Sometimes you can't predict whether you will help or hurt a coin until you try it--you may end up happy or regretful. If in doubt, don't mess with it. You can always try to clean it up later.

To be honest, I don't know what the attraction is with Verdicare. Some people swear by it. I've tried it a couple of times and thought "meh."

Most coins will be just fine in cardboard/mylar 2x2 holders. Other people prefer clear plastic flips or paper envelopes. I don't think there's much difference in terms of safety or preservation; it's mostly just personal preference.

The only thing you want to avoid is long-term storage of silver coins in soft plastic flips that contain PVC. The PVC can damage the surface of the coin over time. If you like clear plastic flips, use archival-grade mylar flips.

 

Hey Joe,

I think my brother has it on a shelf on top of a silica gel pack. This was a couple years ago and the BD hasn't returned.

Erin

 

Cool! Glad it's a healthy specimen. It looks awesome! Do you know what it was from, how hold, etc?

 

Thanks!

Oh my goodness, I can't remember. It's from a life-size statue. Probably 2nd-3rd century-ish, maybe? It was found somewhere in Europe. I'll have to ask him where exactly.

Erin

 

It is possible that the metal is breaking down in structure. Was it buried when found? Bronze left too long in moisture( More than a year) can start to break down and corrode. It's a balance. Sometimes you gotta say this is too much fiddling around. Think of the hours wasted screwing up some old bronze. It's not the most stable of alloys.
The sequi stuff is good. I use less 1 or 2% inain small glass Tupperware and change water daily. I mean whynot it's just distilled water and it seems to work? One can see the BD shrink then disappear. The rest of the coin seems fine. It's basically an alkali that binds up the cuprous metal. That's why you keep changing the water because negative ions will continue to draw salts away from the surface....I think. Anyways keep the coins wet for a week with distilled water. I've seen bronze coins can become bluish in patina but I think it's not major. I usually am only trying to help a coin that is getting the BD. Then hopefully have it slabbed and returned. Anyone know if BD can continue in a slab, even though it's airsealed?