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I have recently got a custom-made ring from a jeweler. It’s made from a byzantine-period bronze ring enveloped in a gold bangle. The bronze ring is “glued” onto the gold ring through some kind of resin, as far as he told me. Would bimetalism with rhe corrosion of the bronze ring happen? Thank you! enter image description here enter image description here

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Moist air, rich in an electrolyte (salt particles) or human contact, providing both NaCl and H+ may supply the reagents needed for galvanic corrosion, with dissimilar metals in direct contact. This usually proceeds, albeit slowly, over time.

Note, exposure to fruit juices could be especially problematic, resulting in a matter of days of continuous contact in the presence of moisture and oxygen, in some visible signs of disfiguring pit corrosion.

Nevertheless, I recommend wearing the ring and enjoying it, but perhaps placing it in fresh distilled water (remove O2 exposure) at night after washing it with mildly alkaline soap (to clean off salts and neutralize body acids). If the vessel use is made of Aluminum, a very active anodic metal, the ring should do just fine.

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  • $\begingroup$ I will try to place it in distilled water at night, as i really care about this ring. But why should the vessel be made of aluminum? $\endgroup$ Mar 16 '20 at 14:10
  • $\begingroup$ @DanteAndrei Well, you're worried about galvanic corrosion right? Aluminum is a metal too. Bronze loses to gold, but aluminum loses to bronze. It's a meat-shield for the bronze against the gold, so to speak. But aluminum develops a passivation layer which is why aluminum doesn't rust and passivation layers tend to do just that, prevent the material from reacting so I am not sure how effective it would be. $\endgroup$
    – DKNguyen
    Mar 16 '20 at 19:18
  • $\begingroup$ But I would actually recommend baby oil/mineral oil instead of distilled water Distilled water isn't conductive until it has solutes in it which your ring will introduce. $\endgroup$
    – DKNguyen
    Mar 16 '20 at 19:23
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If it is maintained in air, no corrosion will happen. If it is maintained in water, and specially in salty water, the bronze part of the ring may be oxidized and will darken. Golden parts will not be modified.

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  • $\begingroup$ So it will only darken? It won’t get literally eaten away? If this is the case, then i’m really happy! Will keep it away from water as much as i can. $\endgroup$ Mar 16 '20 at 11:29
  • $\begingroup$ Yes. It will only darken with the time. And if you want to be sure that no darkening happens at all, you may cover it with a colorless varnish like the one used by pretty girls to make their nails brighter. $\endgroup$
    – Maurice
    Mar 16 '20 at 16:57
  • $\begingroup$ Haha! I’d like it darkened though, to get a patina. As long as it doesnt compromise the artifact. But why wouldn’t it get corroded through bimetalism? Because i know there is a big potential difference between gold and bronze. It’s the first time i have heard of this phenomenon and i’d like to understand how it works $\endgroup$ Mar 16 '20 at 17:12

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