Zinc, How to Tell?

[steve4102]

I purchased some lead ingots that are supposed to be from COWW. When I melt these ingots down, how do I tell if there is zinc in the mix?

[captaint]

Welcome Steve- If what you have is clip on WW's, when you melt it there shouldn't be too much junk on top of the melt. Some, but not a lot. And it should skim off and leave clean shiny lead on top, for a few minutes anyway. If you do have zinc, there will be way more junk on top and it will not skim off easily and leave nice shiny melt. Good luck. Mike

[muskeg13]

If the ingots are fairly soft, this is an indication there's probably not much zinc in the mix. Drop a few onto a concrete surface and listen to the sound they make. Normal lead WW will hit with a thud while zinc will be more of a ping. To really test the ingots, put a few drops of muratic (hydrochloric) acid on a flat surface on an ingot and see if there is any reaction. You should see discoloration and bubbling with a zinc alloy, while there will be no reaction with a lead alloy ingot.

If you decide to melt a few, zinc will require a higher temperature than you're used to when melting lead ww. Like captaint says if you can get zinc alloy to melt it will form a lot of dross on the surface and will be very lumpy with a kind of oatmeal consistency.