International prices, which have shot up more than 10 percent since the sanctions were announced, will have to rise further to lure exports from China.
Timis's Pan African Burkina Limited (PAB) acquired the rights to the Tambao mine, which it says holds 100 million tonnes of manganese reserves, in June 2012.
The Responsible Mining Index, launched in Geneva on Wednesday, assesses the policies and practices of 30 large companies that produce 25 percent of mined commodities, from gold to copper and coal, operating in more than 40 countries.
The LME will suspend Rusal's aluminium from its list on April 17 after some members raised concerns about settling LME contracts with sanctioned companies.