The deposits, estimated to contain 2bn t of iron ore, are cut into four blocks and thought to be one of the world's largest undeveloped iron ore resources.
Development of blocks 1 and 2 will require SMB-Winning to construct a 650km railway across Guinea and a deepwater port on the country's coast for the export of ore from its 60-80mn t/yr Simandou project. But the costs would come in considerably higher than a shorter alternative route via Liberia.
The Chinese-led consortium is Guinea's largest producer of bauxite.
In 2014, the Guinean government stripped BSGR, a joint venture company between Brazilian mining firm Vale and Guernsey-based BSG Resources, of its mining licence for the blocks, citing alleged corruption. The following year, Vale transferred its 51pc equity stake in the joint company to BSG Resources.
UK-Australian mining company Rio Tinto has held blocks 3 and 4 at Simandou for many years, but been unable to make the development stack up and took a $1.8bn write-down on the project in 2015. A non-binding agreement that Rio Tinto would sell its entire Simandou stake to Chinese state-controlled metals group Chinalco lapsed in October, two years after it was initially signed.