In 1917, L.S.S.O’Malley described the coalfields in the upper reaches of the Damodar as follows: “Near the western boundary of Jharia field is that of Bokaro, covering 220 sqmi , with an estimated content of 1,500 million tons; close by… is the Ramgarh field (40 square miles), in which, however, coal is believed to be of inferior quality.