What is this stuff??????

[carl]

Not sure exactly where to ask this question but I'll try it here. I've been casting lead figures for well over 50 years. I acquire lead from numerous and varieous sources such as gun ranges, fishing weights, tire balancing weights and lead acid auto batteries. All this lead has been melted together over the years many, many times. Now here is the question. No matter how many times I melt some of this lead there is always a substance left over on the bottom of the melting pot after all the lead is poured off. I've tried increasing the heat to see if it will also eventually melt but that usually only means a small additional amount of lead squeses out of that residue. The substance on the bottom slowly turns black and when it cools I discard it.
So what is it?

[Prince August]

carl said:

Not sure exactly where to ask this question but I'll try it here. I've been casting lead figures for well over 50 years. I acquire lead from numerous and varieous sources such as gun ranges, fishing weights, tire balancing weights and lead acid auto batteries. All this lead has been melted together over the years many, many times. Now here is the question. No matter how many times I melt some of this lead there is always a substance left over on the bottom of the melting pot after all the lead is poured off. I've tried increasing the heat to see if it will also eventually melt but that usually only means a small additional amount of lead squeses out of that residue. The substance on the bottom slowly turns black and when it cools I discard it.
So what is it?

Its oxidised metal, you should dispose of it at your local amenity centre. It toxic so do not burn it black.