Although the moai look very similar, few are identical. The moai were carved out of basalt. Each had a number of common features: a long and snubbed nose, prominent cheekbones, fine and joined lips, a prominent and pointed chin and in most cases large ears. Over the years the form and styles of the statues have changed.
The tools used for carving were also basalt but of a harder material. Various estimates have been made as to the amount of manpower required to carve out each statue. One of the estimates, was that it took some 30 men working 8 hours a day for a year to carve the moai and topknot. Other estimates suggest that it might take more than 90 men to prepare a road and transport the moai to its site in about three months. The conclusion therefore is that this process was hugely labour intensive.
The round donut-looking topknot are carved elsewhere. This is done near the quarry at Puna Pau where the black basalt is replaced with a porous red volcanic rock. These topknots, the larger ones weighing up to two tons were lifted onto the moai once they were in place. As there are considerably less topknots than bodies, it seems possible that these may have been a later development of their culture. There are still about 25 topknots located near the Puna Pau quarry.
Most a of the figures are men but female forms have been found.
The sizes of the moai vary considerably. The smallest found erected is only 1.13 meters and the largest erected is 9.94 meters high. The largest figure is a 21.60 meters prone figure that still remains in the quarry. It has been estimated to weigh more than 180 metric tons.
The white part of the eye of the statutes is made from white coral and in those that had them the iris was carved from red scoria. The eyes were only added to the statues after they had been erected in place on the ahu.
