Sculptures made during the course of almost eight hundred years (from the late 5th through the 12th centuries A.C.) in an area today comprising the eastern Indian states of Bihar and West Bengal as well as the nation of Bangladesh were carved from a dark grey or black stone; this material is variously identified but it is generally assumed to have come from the Rajmahal Hills in eastern Bihar. This assumption has been tested by a petrologic examination of samples from sculptures of known provenance as well as samples from possible quarry sites. Although work is still in progress, results show that 1) stone from the Rajmahal Hills, a basalt, was never used for any of the sculptures; 2) the sculptures of Bengal (that is, both West Bengal and Bangladesh) were consistently carved from a single type of stone, a chloritoid phyllite; 3) the sculptures of Bihar were carved from a number of different stones.