Retaining colour of re-melted silver

Hi - thanks all for previous help

I was melting down some sterling silver castings - pieces that
didn’t work, sprues etc and cooled them in a steady stream into a tin
of water. Of course these made some wonderful shapes but I was
intrigued to find a lovely gold/bronze colour on the surface of the
silver. I assume this is the copper component of the sterling silver
and because it was in water it was untarnished (I tried the same
cooling out of water and it was black). I have left those out on the
bench for over a month and they haven’t tarnished at all. My question
is how do I use this colour? I realise I could just use some of the
odd shapes, but I wondered about using it in defined shapes - any