Heat the stone to the target temperature and let it melt to reveal the gems inside.
Each stone has a melting target value. You need to keep the temperature of the stone to the exact target value by eliminating the temperature ball flying to the stone by tapping it. Only by accurate calculation can the stone be melted. After the stone is melted, you can get the gems inside. If the temperature is less than 0 or it is bigger than the target temperature, the game fails. Come try how many gems you can collect.