Do I have contaminated lead?

[Desertbuck]

This particular batch was given to me & I was told are under the impression it was 100 percent pure. But it's taking an abnormal amount of heat to melt it the setting on my pot is usually around 6 or 7 it took 9 or max to get this stuff to melt also it left some kind of a greyish orange dust on top which I'm used to but not this much. Also I used a little bit more tin than I'm used to, It casted wonderful 58 caliber mini boolits. But should I be concerned with them they're soft enough to scratch with my thumb nail.
I emptied the pot back out and replaced my usual alloy and it did melt with the setting of 6. Tell me what you guys think contaminated or not? And if contaminated what kind of contamination. I don't think it's zinc.
I'm actually wondering if there's silver in it?

[JSnover]

Pure lead would melt at a higher temp though I'm not sure if you would have to go from 6/7 to 9. Being very soft would also indicate pure lead. If it does contain silver there is not enough to worry about.
what did it look like before you melted it? Lots of oxidation?

[Desertbuck]

Nop the bars came out nice and shiny and stayed that way until I use them today they weren't dirty at all I cleaned the melt very thoroughly.

[jsizemore]

Sounds like you got close to pure Pb. Fill out good at the higher temp? A little tin helps? If both those work then you got it under control.

[georgerkahn]

I might try a lead hardness tester (e.g., the SAECO, LBT. or similar). From the reading you get may give an indication re the alloy you have. I've gotten all sorts of residue/flux -- more in the smelting pot than casting -- but that orange dust is a new one to me. Fe203 is iron rust, but that's reddish. Perhaps to inquire to a chemist may be the way to determine what might give that color. Wish I could help...
BEST
george

[Yodogsandman]

Was your pure lead from dirty pipes? Maybe calcium deposits that weren't fluxed and cleaned out?

[Desertbuck]

Was your pure lead from dirty pipes? Maybe calcium deposits that weren't fluxed and cleaned out?

That could be a possibility the majority of lead was given to me by my father who got it from a customer while drilling a well who apparently knew I was boolits caster. The lead was two round ingots attached to each other with a slab of leadin the center. They were very gray I mean very very gray almost to the point of being black, also I threw in numerous fishing weights when I smelted this batch.
My father also told me that the man said there's more where that came from and if I wanted more he'd be willing to make a deal.

[bangerjim]

The only way you will know for sure is to take a hunk of it to a scrap yard and have them shoot it with an x-ray gun to get a % make-up. If you have a lot of it, it will be WELL worth it!

Otherwise you (and all the rest of us) are just guessing.

banger

[triggerhappy243]

I had that same dust come out of my lee pot... And it kept coming out.more and more

[runfiverun]

lead oxide is orange/yellow in color. [with a tinge of red in the shadows]
I used to use it when I worked in electro-ceramics.

[coffeeguy]

We have a winner! Second guess would be some kind of sulfide/sulfate contamination like from a melted down car battery. Flux with sawdust, reduce with beeswax or paraffin, flux once more and skim and you'll be good to go.

[Dusty Bannister]

Why not just contact the guy selling the lead and see what he has to say? Adding sinkers of unknown alloy? Might that have been the source of the dross? If it casts well, and shoots well, and is priced right, there is not a lot to suggest a reason for not buying it.

[Desertbuck]

I like the boolits this lead made. I was just a bit concerned of the gray crust on top of the melt.
But after a little bit more research and as some of you said its nothing to worry about. All my other lead was wheel weights and range scrap, this is my first time with pure lead.

[Defcon-One]

I've had the same thing happen with Pure Lead from drain pipes. As long as the bullets are nice, I would not worry too much. Hotter temps will cause this type of oxidation, especially with Pure Lead.

One thing that I would do would be to skim off the dross and dispose of it properly as soon as you are done casting. Don't keep it around. Don't store it in air tight bags and don't let it get wet and sit around.

As long as the bullets are shiny, well filled and soft enough for your application, you should be good to go!

DC-1

[jonp]

Yellowish orange has me thinking sulfate of some type

[jsizemore]

When you see that again you need to stir and scrape your pot more then usual. The higher heat necessary to cast good boolits will cause more dross to release and if you let the alloy level drop too low will possibly plug your spout. That dross does act as an insulator to cut down on oxidation and heat loss.

[Nicholas]

Yellowish orange has me thinking sulfate of some type

The pure sulfate of lead, anglesite, is white. One of the many mineral oxides of lead, massicot, has a yellow color. See wikipedia.

[jonp]

Sulfate as in sulfer

[mold maker]

How do the weights compare with what your used to?