lead, tin, and zinc can all be melted with a torch in quantities appropriate to the size of the torch
all three will produce poisonous vapors if heated too much
lead is the only that is easy to get a couple of dollars a pound at hardware stores and plumbers supply
it can be melted on a kitchen burner but will ruin the pan you melt it in for cooking and if you spill it, it burns into the skin with a lot of heat
as to how hot - look up the boiling point on line, but you probably won't be able to get there with a kitchen blow torch.
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or were you asking what a kitchen blow torch costs? Just an after thought which makes your question inept.