Howdy all! My first time back in a long while due to work schedules and severe lack of time.... and boy do I have an oddball question for the group. I have done a search both on google and here but the results are a bit lacking. I'm not sure if it's my choice of search terms or what.
I have a pile of "lead" from the local scrap yard- most of which is in the form of weights for diving and such. I had just finished melting down about 57 pounds of range lead and casting small ingots in stainless condiment cups and I decided to do the same with the weights. They melted almost instantly in the cast iron skillet! Not thinking much of it I started pouring it into the cups. 10+ minutes later the molten metal had not solidified. I immediately figured I had a mix that was not optimal... lovely. Somebody had turned in homemade dive weights that weren't exactly lead. I ducked into the house and grabbed an aluminum foil pan and proceeded to pour the metal into it. Same exact results. The metal took forever to solidify. After almost 15 or so minutes I checked on it and it had hardened on top but there was still a large quantity of liquid under the surface.
My question is this- what the heck is it? Is it a high concentration of tin? From what I've been able to piece together tin lowers the melting point but will increase the hardness. This makes some sense as I could almost comfortably touch and hold my fingers to the side of the foil pan after 15 minutes, the aluminum dissipating a large portion of the heat.
What do I do with this horrid mix, without being able to pinpoint exactly what it is? I have been casting for 9mm and .45 ACP for a while now with both WW and scrap (pipe, sheeting/roofing, etc) and have not worried to much about the hardness due to powder coat. No leading after several thousand rounds. I've read that with too much tin one ends up with a solder type mix and it's near impossible to remove from barrels and such. I'm worry about trying to use even a small amount of this unidentifiable mix in fear of permanently damaging my guns.
Does anyone have any ideas or suggestions?