The 30-share BSE Sensex closed down 671.15 points at 59135.13.: Flipkart cofounder Binny Bansal is in talks to invest about $100-150 million in PhonePe as part of an ongoing financing round at the digital payments company, people in the know said. Blackstone, CVC Capital Partners and Goldman Sachs are among several bulge-bracket global private equity funds weighing bids to buy a controlling stake in the International Gemological Institute (IGI) in a deal that could value the world’s biggest independent diamond-grading firm anywhere between $250 million and $300 million, two people directly aware of the talks told ET.