Need idea for material to pour into wax mold - making a skeleton key
I own a treasure chest, locked with a heavy-duty skeleton keyed lock. However I only have one key. I am trying to make another for it as a spare. I have made a wax mold of the key, but I don't know what I can pour in, to make a key that is not brittle, not flimsy and cold enough it won't melt the wax. Any ideas?