BlackRock Inc., the world’s largest investment firm, has purchased a multi-million dollar stake in a mining firm with a gold exploration licenses in Cambodia. Stephen Promnitz, CEO of Indochine Mining, which is listed on the Australian Stock Exchange and holds a gold exploration license in Kratie and Ratanakkiri provinces, said from Sydney yesterday that BlackRock had bought 9.9 percent of the company’s shares. Still, he distanced BlackRock’s decision from having any link with its assets in Cambodia. … The company has a market capitalization of $77.8 million. Mr. Promnitz said that the company was still exploring its two Cambodian tenements but said he could not estimate when extraction could begin.