Mixing Metals

[Strings]

If you mix metals like copper, stainless still, silver it could be OK. But if you add some less stable metals you can end up with fast corrosion of one of them.

you're thinking galvanic corrosion. I've seen examples of high-end flintlocks where silver was used for the stocks, reacting with the steel or iron of the barrel and creating a problem over time...

[tyger]

Misinformation about galvantic corrosion has been posted before. Galvantic corrosion requires the presence of an electrolyte (footnote below).

As terrestrial beings, there is no reason for us to worry about the combinations of metals that we are talking about. Married metal jewelry will last for thousands of years, as withnessed by treasure found in the pharaoh's toombs!


Mix your metals and live a little!


Footnote:The presence of electrolyte and a conducting path between metals may cause corrosion where otherwise neither metal alone would have corroded. Even a single type of metal may corrode galvanically if the electrolyte varies in composition, forming a concentration cell.

[Strings]

Hmmm... I wonder about the flintlocks I've seen then, if there wasn't some other culprit.

Although I suppose sweat or bodily oils COULD have provided the electrolyte...

[MacLowlife]

The only place I can think of where people are more religious about such things is church. I haven't darkened the door of my church for nearly two years now, but I remember distinctly that they had a bright brass altar rail, brass lecterns, and silver pieces on the altar. If I were you, I wouldn't slap a big golden brass sporran cantle up against a big silver-chrome 3X5 card belt buckle, but anything else would probably do just fine. If it worries you, you can do as one old girlfriend of mine did- get a few pieces that are both "yellow" and "white" and then wear everything else to match them, either the yellow OR the white part. It would be fairly easy to add a brass badge onto a chrome buckle. Then you would be set for whatever came your way.

[MacLowlife]

There is an earlier (closed ) thread on a related subject, from August of 08, entitled Gold Buttons and Silver Accessories. It might be helpful.

[Mipi]

I would just like to add small warning. When you mix metals, you have to be a bit concerned on possible chemistry issues. If you mix metals like copper, stainless still, silver it could be OK. But if you add some less stable metals you can end up with fast corrosion of one of them. I don't know all details.

I would check before mixing metals if they're in direct contact.

Just my 2 cents.


Mipi

[Jack Daw]

I would just like to add small warning. When you mix metals, you have to be a bit concerned on possible chemistry issues. If you mix metals like copper, stainless still, silver it could be OK. But if you add some less stable metals you can end up with fast corrosion of one of them. I don't know all details.

I would check before mixing metals if they're in direct contact.

Just my 2 cents.


Mipi

Who told you?

[Mipi]

Who told you?

I'm electro technical engineer and we used to do some experimenting with galvanic elements in the school. OK, if this is a part of your garment, reactions are rather slow, while there is not so much electrolyte available, but still…. And it greatly depends on the metal combination.

It was meant just as a minor warning.

[turpin]

Here is another fantastic example of mixed metals, courtesy of Tyger. Sterling silver thistle heads on brass.

[Strings]

Flintlocks in question didn't have any wood. IIRC, they were silver stocked with iron or steel barrels...