Assam has abundant mineral resources coal, petroleum, limestone and natural gas are the principal mineral resources. It is also the largest producer of crude oil in India. Other minor minerals include magnetic quartzite, silimanites, iron, ore clay and fredspar etc. Oil India Limited (OIL) is the second largest hydrocarbon exploration and production Indian public sector company with its operational headquaters in Duliajan, Assam. India under the adminstrative control of the Ministry of Petroleum and Natural Gas. Assam is a major producer of crude oil and natural gas in India. It was the second place in the world where petroleum was discovered. Asia's first sucessful mechanically drilled oil well was Makum (Assam) way back in 1867. The second oldest oil well in the world still produces crude oil. One of the biggest public sector oil companies in the country. Assam has four oil refineries located at Guwahati, Digboi, Numaligarh, and Bongaigoan with total capacity of 7 MMTPA (...