You've been asked to locate a gem at the Orapa Mine, the world's largest diamond mine. By sending ultrasound waves deep into the ground, you can determine the location and condition of the gems based on the echoes. Occasionally, the waves bounce off strangely, but as experts, we'll eventually find the gems. Choose one person as the problem presenter. The presenter will be the director of the Orapamine, and the remaining players will become mineral explorers. The player who correctly identifies the positions of the minerals (Tangram pieces) placed by the director wins. Players take turns, starting with the player seated to the left of the director and proceeding clockwise.