Mining giant Rio Tinto has joined the China Beijing Metals Exchange (CBMX), a new electronic trading platform providing additional iron ore trading channels in the Chinese market.The CBMX brings together buyers and suppliers of commodities and is thought to offer better transparency than existing market, according to The Sydney Morning Herald.We welcome the development of CBMX as it gives us a new option for selling any available tonnes to China, over and above those already contracted," said Rio's Iron Ore Asia President Alan Smith.Rio Tinto Iron Ore Asia markets iron ore on behalf of Rio Tinto to Asian customers. It signed an agreement in Singarpore earlier today between senior officials of CBMX."We look forward to the Exchange developing into a transparent, independent, efficient and sustainable iron ore trading platform supported by broad market participation," Smith said.BC