Alternative plan: whip out the blow torch, and play it gently and evenly over a steel one, until you get your desired tone. The steel goes straw-coloured, then a steadily deeper orange into bronze, then onwards through various colours. Make sure to let air get to the metal as you go along, else you may take it too far before you realise. And there's no going back - although I suppose you could sand off the surface and start again...