Gold color/film on pure lead melt

[fingers284]

I have smelted a few hundred lbs of co ww over the years and the melt ,after a dross skim or two and a flux or two is always the shiny silver color that I " think" is normal. I recently lucked onto a roll of "used" roofing lead, about 150 lbs or so. The lead had a considerable amount of old dry paint and other "foreign" materials stuck to it. This melt, after skimming and a few "fluxes" with copious amounts of sawdust always has a gold colored tinge to the surface, I can skim it off but it almost immediately returns, my question is " is this normal for pure lead or often seen and nothing to be concerned about.

This is my first time smelting what I think is pure lead and have another 300 lbs or so that I assume is pure from a dismantled x-ray booth.

[tradbear55]

Yes, gold color and/or blues and purples. I get it on pure lead melts when casting for my muzzleloader. It's normal.

[comprschrg]

The same thing happened to me, exept I had some blueish purple color also. Then yellow dust, powder was stuck on the sides of the pot. No matter how much fluxing with every known flux, and heat range. My "pure lead" was from the left overs from a x-ray room. It had sheet rock paper glued to it.
Lower melt temprature helped. Just above melting. I thought it was calcium or stontium from a maintenance free car battery. When I added just a bit of tin, it seemed to fix everything. I never really felt I figured to out.

[badbob454]

yes ....... good clean lead has a lot of color lots of blues and purples as well as gold/// ps leave the car batterys to the professionals lots of hazardous metals in there .. only the posts are safe

[OS OK]

I've seen it on a few occasions, who knows? Could be some other metals that get in the mix as these flashing manufacturers make the sheets up and reclaim lead using...we don't know what?
One answer may lay in the fact that we may get out pots too hot trying to melt everything too quickly, thereby possibly melting other metals that have a higher melt point that are suspended in the dross. They may be less dense and show up on top.

Dang good question though.

[runfiverun]

gold=tin

on pure lead you'll see a rainbow swirl of purples/blue/gold.
and the ingots will have a bluish tint to them.
but just gold is tin oxidizing out of an alloy.

[fingers284]

gold=tin

on pure lead you'll see a rainbow swirl of purples/blue/gold.
and the ingots will have a bluish tint to them.
but just gold is tin oxidizing out of an alloy.

so I guess its not a good idea to try to 'skim' it off anymore. LOL

Thanks guys

I would have some WW to mix with the pure but I think, when smelting the WW my melt got hot enough on me to also melt a few zinc weights in it as well so will have to find a source for some tin and antimony.

[OS OK]

I re-run all that metal dross (from the pour pot) in the next batch of scrounged lead mix, you would be surprised how much goes back into the new pot-O-lead.
Best by far in my shop, is to keep it covered in sawdust by starting with a full cup full or more of sawdust in the bottom of the pot even before all the scrounged lead starts to melt. This way it doesn't get a chance to oxidize while the batch slumps in. When you pull all that sawdust off with the rest of the dross and dirt...you are staring into mirror clean lead.

[fingers284]

You know what, I've thought of doing that but thought the little bit of "silver drippings" skimmed off a melt was so insignificant that it wasn't worth the effort but after reading your post, it stands to reason that those skimming's would contain a large % of the stuff we try to flux back in & use to make lead more palatable in a mold...thank you for that.