International smelting technology symposium (Incorporating the 6th Advances in Sulfide Smelting Symposium) ; Proceedings of a symposium sponsored by The Metallurgy and Materials Society of CIM and the Pyrometallurgy Committee of the Extraction and Processing Division of TMS (The Minerals, Metals & Materials Society), held during the TMS 2012 Annual Meeting & Exhibition, Orlando, Florida, USA, March 11-15, 2012