Weirdness in my Lead Pot -

[Oyeboten]

Hi all - help me out here please, what IS this thick, firm, pale "Pea Soup" green stuff forming on my molten Lead???

Once broken up and cooled it goes more yellow color with some pale Orange in it.


Hosted on Fotki

Smaller "LEE" Electric Smelter ( has two Molds heating on it's top edge )...

I plugged it in and let it sit a little while to come up to heat, and this mysterious pale green color stuff had formed on top. Since last use, it sat close to full, and had been merely a pale grey on top.

It was a very firm crust, and I thought the Pot had chilled, but I was able to wiggle the Ladle Handle and get the crust broken up and spooned off.

I cast 150 Boolits, adding more Lead and Tin now and then, took a fast break to make some Coffee, poured the first possible cup, walked back out, and it had formed again! Same thing, this is when I snapped the picture.

The crust was about 3/16ths of an inch thick and VERY hard and firm, I about could have lifted the entire Pot by the Ladle Handle.

What IS this stuff?

This never happened before - I am using same batch of Lead...supposedly Pure Lead, to which I add about 5 percent Tin.

I use clean Wood Lathe Shavings to clear the dross now and then.

[onelight]

Never had anything like that in my pot.
Where did your lead come from ?

[Winger Ed.]

The gray is normal oxidation.

I've never seen anything quite like that happen to me, but what ever weirdness and evil spirts that float up in mine
I just rake it off and keep going.

The oddest thing I ever had come up was a bunch of what I later learned was Cadmium.
I also learned its about 50% by weight-- pure cancer.
I raked it off too.

[DukeConnors]

that is strange. it looks like mac n cheese

[Oyeboten]

Never had anything like that in my pot.
Where did your lead come from ?

Lead I got off ebay some years ago.

Am about half way through it, and this is the first time anything like this happened.

So, this weird 'Sage Green' or pale 'Split Pea Soup' color Crust formed once the Lead Pot was up to heat on initial warm up today, forming over what had been merely usual old dull grey cold Lead left in the Post from last time I was casting, some days ago...I broke up the crust, spooned it off, then was casting a while...no odd anything formed, I merely tossed in some clean Wood Lathe Shavings once in a while to help clean the Dross away which I remove with a Spoon.

Then, deciding to make some Coffee, I was only away from the Pot about 8 minutes maybe, just long enough to start a little Pot of Coffee and to pour the first small Cup, and I walked back out, and that Crust had formed again.

Of course, the bunch of small Ingots I got off ebay, maybe they are not all consistent in what is in them...but, everyone so far though is soft, and a finger Nail can make a decent mark on the edge...and they were all bright and shiny when I got them, but they have gone dull grey from sitting outside a couple years.

[Dan Cash]

Winger Ed mention Cadmium which crossed my mind straight away. I have never smelted Cadmium but I surely would find out what is in that alloy before I went further. People on this forum obsess over lead vapor but that is hard to create. Cadmium, on the other hand, found in lead-acid batteries will melt and produce a very deadly vapor with little effort. Stop using that alloy until you know!

[Winger Ed.]

Stop using that alloy until you know!

Its long gone.
I had a customer back then that was a metallurgical engineer.
He pointed me in the right direction with it---- back to the scrap yard.

[Dusty Bannister]

Is that a casting ladle that is sort of glowing orange? Is it possible that your heat control has failed and is stuck in the full "on" position? A thermometer reading would seem a good idea, if you have one. Yellow and tan dross, unless very overheated, is probably just trash in the alloy. If the dross does have anything unusual in it, do not put it in a closed damp container as toxic gases could result.

Now that you have cast some bullets, weigh several and see if they are about the normal weight for a known good alloy.

Just a question, has anyone had a melt contaminated with chamber casting alloy? That would be soft, and probably create a lot of dross when over heated to normal casting temps. I do not know what colors might be involved.

[Oyeboten]

Winger Ed mention Cadmium which crossed my mind straight away. I have never smelted Cadmium but I surely would find out what is in that alloy before I went further. People on this forum obsess over lead vapor but that is hard to create. Cadmium, on the other hand, found in lead-acid batteries will melt and produce a very deadly vapor with little effort. Stop using that alloy until you know!

Okay...

I had a nice Breeze blowing from the right side so any fumes or smoke from the Lead or from the occasional Wood Lathe shavings, went straight to my left, and nothing to smell from where I was sitting...I sit well away, and reach far when casting.

I have to suspect some of the Ingots must have some odd and likely "not good" low melting point something in them for this to have happened.

I have no connections to allow me to have any sort of analysis done, other than to google some Lab and Mail them a sample.

I had got about 20 Pounds I think, ( several years ago ) and have gone through about half, with nothing unusual, till today...all the ingots look the same, color wise.

I'll give these remaining ten pounds or so to some scrapper, and start fresh, and hope for the best with the next round of new-to-me Lead!

[Oyeboten]

Is that a casting ladle that is sort of glowing orange? Is it possible that your heat control has failed and is stuck in the full "on" position? A thermometer reading would seem a good idea, if you have one. Yellow and tan dross, unless very overheated, is probably just trash in the alloy. If the dross does have anything unusual in it, do not put it in a closed damp container as toxic gases could result.

Now that you have cast some bullets, weigh several and see if they are about the normal weight for a known good alloy.

Just a question, has anyone had a melt contaminated with chamber casting alloy? That would be soft, and probably create a lot of dross when over heated to normal casting temps. I do not know what colors might be involved.

Lol, no, not glowing Orange, but it did turn Orange from what-ever was in the Lead.

It has stayed same color now that it is cold.

My Molds are clean...or, one, had some minute traces of Axle Grease, but it never got in to the Lead or bothered anything...and it more or less cooked off right away anyway.

[Oyeboten]

Could Sulfur contamination do this? Like if some of the Ingots somehow had Sulfur in them? Or if they had been melted down from old Car Battery Plates and Terminals?

Or...could Sulfur combine with Lead Oxides or even promote their formation in odd ways, in a way which would maybe create that oddly textured, pale Green crust?

Background in the image I posted, you can see the chunks of earlier crust in a small Glass Custard Dish, 'dross' Dish, and it changed somewhat to be more of a Yellow color from sitting.

[kevin c]

Cadmium salts are yellow, red and orange, and the colors are intense enough that they have been used, diluted down, in artists pigments. They are considered toxic.

Could be some cadmium contaminated battery lead in some of those ingots. You're wise to not use them.

[Conditor22]

Cadmium
Chemical element
DescriptionCadmium is a chemical element with the symbol Cd and atomic number 48. This soft, silvery-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Wikipedia

Cadmium/Melting point 609.9°F

[Oyeboten]

Here is a piece of the hard, heavy crust material -

Greenish on top, yellowish below...

Hosted on Fotki

Hosted on Fotki

[Oyeboten]

I wonder what Arsenic would do in the Lead Pot? And if this may be Arsenic? It's Oxides I think are yellow.

Glad I had a nice breeze anyway!

[Teddy (punchie)]

looks like build up I took off of the side of the lee pots I fired up. A caked up build up that look like sulfur.

Did they mixed dross back it the the ingots ??.

[NyFirefighter357]

Cadmium salts are yellow, red and orange, and the colors are intense enough that they have been used, diluted down, in artists pigments. They are considered toxic.

Could be some cadmium contaminated battery lead in some of those ingots. You're wise to not use them.

After reading the original post I did some research and came up with lead(II) chromate (PbCrO4). American school bus, painted in chrome yellow. I concluded that the lead was probably melted batteries and the contamination regardless of the source is likely very toxic and possibly a carcinogen.

[ioon44]

What was the temperature of your pot and how long was it at that temperature?

[Oyeboten]

Previous times Casting, ( five casting sessions I think, over the last 8 months or so ) same Pot, same Ingots, never had anything remotely like this.

Yesterday, Cold full Pot from when-ever I had last been casting, surface of cold Lead merely a dull grey...I plugged it in, set the two Molds on it for them to heat up, let it come up to temp for 20 minutes maybe, tops...and, when I came back out, the mysterious thick 'Split Pea Soup' texture crust had formed.

I thought the Pot had shut down because the crust was so strong it made it seem like the Lead had solidified, the Ladle was frozen in to it, but wiggling the Ladle Handle I realized the Lead was Molten under the crust and I broke the crust up in to chunks and cleaned off the Lead.

Ingots had never shown any sign of any dross in them.


So, Casting a while, added more Ingots as needed, took a little Break to make some Coffee, poured first small Cup out of the Mr. Coffee Carafe, came back out, and, the mysterious Crust was once again present.

No crust or related materials had occurred while I was actively casting...only the minor thin dross as always, which I deal with via some clean Wood shavings, which I then stir in well and spoon off the dross.

In my interest to have about 5 percent Tin, to the ( supposedly ) 'pure' Lead of the Ingots, I would add a small piece of Tin, which was about 1/10th of a Lead Ingot's worth, when adding two new Ingots, then stir well with a Spoon.

Pot Temp is just enough for my Molds to be agreeable, and I had originally had things too cool when learning to use the little Electric Smelter, gradually increasing the temp in small amounts to find where the setting would allow the Molds to be right temp, with a 20 minute warm-up of them sitting on the Pot Lip.

This has worked nicely, and Bullets have been filling-out well in the Molds.

So, all told, I'd guess the Pot was up to temp for about two hours or so.

Crust never happened while I was sitting there, only when I would take a little break for a few minutes, or, initially, when I was in here letting the Pot come up to temp and for it to also warm the Molds, for me to begin Casting.

[Oyeboten]

I do not know what the Temperature was/is in terms of degrees.

It is a smaller 'Lee' Electric Pot, and the Temp setting is set to 8-1/2.