There are actually seven different tests that can be performed in the shop to identify materials. They are: appearance test, fracture test, spark test, torch test, magnetic test, chisel test, and hardness test. Rather than a very long post, I sent you an e-mail describing each method of testing. Also, If you resort to test welding, remember that lead dust and fumes are poisonous, so exercise extreme care.
Try a product call LeadChek, though I have never used it to identify lead steel.
You squeeze some fluid out onto the tip of a swab. Rub the tip of the swab on the surface to be tested. If the yellow fluid turns pink... , it's lead. Abot $3.00 for a package of two swabs.
I buy in the paint department of Lowes and HomeDepot.
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Another Test
I must caution you that adequate safety procedures must be followed.
If you have a chemistry laboratory at your school, have someone trained in safety chemical handling procedures, such as the chemistry instructor, perform this test.
1. Immerse the sample in warm nitric acid (50% v)
2. Add one drop concentrated sulfuric acid to the nitric acid solution. A white precipitate indicates lead.
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