Lead Blocks - Composition Help

[davrey]

I picked up some rectangular lead blocks at the scrap yard. They called it "clean" lead. Each block weighed in @ ~20lbs. I have no idea on composition. Pure lead? I also got a smaller one with 45 degree notches in it on two sides. Clearly this was made for a purpose. Any thoughts would be appreciated? Am new to casting and this site.

[454PB]

Without a hardness tester, it takes a little experience to "guess" at what the alloy may be. We generally say that if it can be scratched by your fingernail, it's dead soft. If you have access to an accurate thermometer, finding the melting temperature will tell you more.

I've never heard of "clean" lead, but they may be counter weights of some kind. The counter weights I've found were always pure or nearly pure lead.

[runfiverun]

lead bricks sounds right.
drop them on their corner on the cement at a height of about a foot and listen carefully for a tuud sound.
if all you hear is tudud you got lead.

[Beerd]

and if you hear "Yyyeeeeooooow" you got our toe. :-D

probably counter weights, treat it as pure lead.
..

[davrey]

Thanks guys.

[btroj]

I have some lead bricks that were designed as shielding for lab experiments. They are pretty much pure lead.

[Moonie]

There is a formula I've seen posted before that uses weight and volume to determine the composition, it only works with binary alloys though. It should show you if it is close enough to pure to consider it so.