Bituminous coal | Properties, Uses Formation | Britannica
Highvolatile bituminous coal is classified on the basis of its calorific value on a moist, ashfree basis (ranging from 24 to 33 megajoules per kilogram; 10,500 to 14,000 British thermal units per pound), while mediumvolatile and lowvolatile bituminous coals are classified on the basis of the percentage of fixed carbon present on a dry, ashf...