Odd looking ingots

[fivestring]

I melted some roof flashing. I noticed the melt had a multicolored skin on top. when it cooled in the muffin pan it shrunk significantly and got a galvanized look to it.

194024

The ingots came out very shiny.
194030

The one on the left is ww. The one on the right is the roof flashing. I used a spring loaded punch to test hardness. The roof flashing seems softer.

What is this substance? Can I cast it?

[KenH]

WOW - that's interesting. You might shouldn't cast bullets with that stuff without MUCH more testing. Just ship a big box of that stuff to me and I'll do the testing for you with 45-70 bullets and let you know how it works :lovebooli :)

[runfiverun]

you got lead there.
it might have a little something else in it but it's probably a 6-7 on the BHN scale.

[308Jeff]

I recently melted a brand new roll of roof flashing. Mine also took on the multi-color look. WAY more than any other lead I've melted.

[rancher1913]

looks like your melt temp got a little high. high temp will cause more shrinkage as it cools.

[fivestring]

Ok. Good to know. I have another 30 lbs or so to smelt. I guess this is the first time I had anything purer than ww to melt.

[KenH]

Oh well - guess I don't get any lead to test:p

[fivestring]

Probably not. Thanks guys.

[6622729]

Next time you melt something down like this, try to reduce the heat. You wouldn't want to get too overtemp when melting something unknown to avoid letting zinc or some other contaminant an opportunity to get in there. In this case it simply looks like too much heat. You'll sometimes get a bluish/purplish color in close to pure lead alloy.

[Wayne Smith]

Used to be a sticky - Blue and Purple and Gold, Oh My about exactly this.

[Harry O]

Many years ago I bought about 800lbs of roofing lead that was salvaged from buildings built before 1900. It had the color you mention. I cut it up and melted it down into ingots. When I got a hardness tester (actually ended up with 3 different ones eventually) I tested several of them, the Bhn was LESS than 5.0, which is what pure lead is generally said to be. The average test was about 4.7 to 4.8 Bhn. I have since learned that chemically pure lead has a Bhn of about 4.5. It is good stuff to start with.

[gwpercle]

That's what pure , or nearly pure, lead looks like when it cools. And the rainbow color is also an indicator.

Mix it 50/50 with clip on wheel weights and you will have a great general purpose alloy for casting.

Looks like you scored a Wilton , 1 piece aluminum , mini-muffin pan for ingot mould...that's exactly what I use , good pan .
Gary