NEW YORK ( TheStreet) -- Rio Tinto ( RTP) and Aluminum Corp. of China ( ACH) are in advanced talks to jointly develop the Simandou iron-ore project in the West African nation of Guinea, the Wall Street Journal reports, citing a person familiar with the matter. Rio's agreement with the Chinese company, also known as Chinalco, could offset some of the cost of the projected $6 billion Guinea mine project, the Journal says. Rio Tinto is spending about $10 million a month to develop and explore the mine with the goal of selling the ore commercially, the newspaper says. Rio Tinto last year walked away from a proposed $19.5 billion deal with Chinalco that would have give the Chinese company an 18% stake in Rio Tinto. To pay down debt, Rio Tinto instead held a rights issue and formed an iron-ore joint venture with fellow miner BHP Billiton ( BHP). -- Written by Joseph Woelfel in New York. Follow TheStreet.com on Twitter and become a fan on Facebook.