Reddish color (rusty?) on ingots left outdoors

[flintlocke]

I was given a large quantity 300# or more of lead scrap last year, varied sources, melted it down poured ingots, put it on a pallet and left it outdoors. In this wet winter the ingots show a 'dusting' of rust(?) on the exposed surfaces. The alloy runs around bhn11 or so. Has anybody seen this before...is it anything to be concerned about? I'm too tech challenged to post photos.

[Dusty Bannister]

Common to occur. Most often due to traces of iron in the melt and it does form oxide on the surface. If you remelt and clean the alloy, you will probably have the same result again. Just flux well and remove dross when casting and it is a non-issue. Most likely your lead scrap was from plumbing lead.

[FLINTNFIRE]

Mine had that from wheel weights , I figure it gets a little trace amount of other metals in , where it was stored years ago the mice got in and added a aroma , it will not be a issue just melt and skim of any junk , I toss all the skimmings in my cut off propane tank and it all gets melted with next batch of range scrap .

[flintlocke]

OK, thanks fellas, just as you predicted, the scrap was about 30% COWW and 50% old timey plumbing scrap.

[Winger Ed.]

Give it a few extra stirs when ya flux it.
That and any other trash wants to float up out of the melt.

[LAGS]

When lead is melted in an Iron pot or Cast Iron pot , the pots surface does flake off a bit especially if the pot has rust on it.
That stuff mostly floats to the surface and is skimmed off with the lead dros.
But some will still remain on the surface of your ingots.
Then that iron fist will rust again when exposed to moisture or air.
When remelted , the dirt and minor rust will again float to the surface.
You can lessen this surface contamination by smelting the lead in a Stainless steel pot.
But it isn't worth the extra effort to try an get Pure ingots.

[lightman]

Like the others said, it won't hurt anything. Just flux and skim when you start casting with them.