West Bengal contributes 13.26% of the reserves and 6.49% of the total coal output of the country. Here coal deposits are distributed in Barddhaman, Bankura, Purulia, Birbhum, Daijeeling and Jalpaiguri districts.
Raniganj coalfield lays 183.5 km north-west of Kolkata in Barddhaman and Birbhum districts. The field has a total area of 1,554.59 sq km with estimated reserves of27, 245 million tons (13.90%). It possesses two major coal bearing horizons (Barakar and Raniganj) producing good quality coking coal.
The lower series (Barakar) consists of 7 coal seams of which Ramnagar, Laikdih, Begunta-Ramgarh, Salanpur and Damgaria are important. Of these Ramnagar and Laikdih seams contain good quality coking coal. The upper series (Raniganj) includes 9 coal seams of which the Dishergarh, Sanctoria Ghusick, Poniati and Raniganj seams yield excellent coal. The average thickness of the Dishergarh seam is 5.49 m.
Coal from Raniganj field is of high moisture and high volatile type. It contains 2.81% of moisture, 33.24% of volatile matter, 54.75% of fixed carbon and 15.04% of ash. The estimated reserves upto a depth of 610 m have been 13,618 million tons (27,245 million tones unto a depth of 1,219 m) of which 548 million tones are coking coal. It is mainly a non-coking steam coal used by railways, thermal power plants (at Bandel, Durgapur, New Cossipur, Malajore, Gurapore and Dishergarh). The coalfield has two coal washeries at Jama-doba and Lodna.
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The Darjeeling coalfield lies in the ranges of the outer Himalayas in Daijeeling district covering an area of 48 km between Pankwali and Darling. Coal seams are exposed near Tindharia and in Mahanadi and Mana river sections. The thickness varies between 0.61 m to 3.4 m. The coal is in powder form with coking quality. In Jalpaiguri district a few coal seams are found near the Duars area.