As Anglo American’s board met at the lavish Vergelegen wine estate in South Africa yesterday evening as part of a 100-year celebration, executives were blindsided by news headlines: Indian mining tycoon Anil Agarwal was becoming the biggest shareholder. After Anglo’s managers partied to honor the past, the company now faces an uncertain future. Agarwal is now in a position to push for major change, but his intentions are still secretive, leaving analysts to guess at the billionaire’s plans for the blue-chip mining institution.