what are three physical properties of gold?
["Gold's unique physical properties. ... ", "It's a soft, ductile metal. ... ", 'Gold has a very high boiling and melting point. ... ', "It's a good conductor of electricity and heat. ... ", 'Gold will not tarnish. ... ', 'Gold is a noble metal. ... ', 'Gold is highly reflective. ... ', 'Gold is very heavy and dense.']