Granite mortar in old Copra mill being used as decor in a hotel, Bope, Sri Lanka.

 A 'Copra mill' was a mortar made of granite mounted vertically with a long stalk buried in the ground. There was a vertical pestle made of wood and mounted on a contraption. This heavy pestle was made to rotate inside the granite mortar by being attached to two bullocks which were made to go round and round the pestle. Dried coconut kernel, called Copra, was put into the mortar and the juice was extracted to be boiled and coconut oil and 'poonac' were the raw products extracted. Poonac was dried and used to feed cattle.