 The melting point of a substance is a characteristic property of the substance. Metals melt over a very wide range. Metals like copper melted about 1,000 to 1,100 degrees Celsius. What we have is an alloy of bismuth tin and lead. It has a low melting point. In fact, it melts below the boiling point of water. I've got a spoon made out of the alloy. I'm going to put my spoon into the boiling water.