The Swedish firm is fine-tuning details for a group split that will see its mining, infrastructure and natural resources business trade as a new company in 2018.
Over 50% of the proceeds will be used to fund clean water, electricity, school, medical facilities, bridges and roads, none of which are currently available in the village of Koryardu, where the diamond was found.
Rio Tinto production of refined copper at the Utah-based division has been halted since Oct. 8 after a worker was exposed to sulfur dioxide gases at the plant. The employee died two days later.
Precious metals miner said its platinum group metals (PGM) operations had delivered "solid operational results" in the first-half of 2017, prompting an upward revision to its 2017 production forecast and a downward revision to guided costs.
Company said it expects production of between 50,000 and 55,000 ounces of gold from its new mine in south-western Mali to bring total metal production for 2017 to between 530,000 and 570,000 ounces of gold.