S.S.SANDHAWALIA, J.

1. Whether the industrial effluent commonly known as slurry flowing away from a colliery washery is coal and thus within the ambit of the Mines and Minerals (Regulation and Development) Act, 1957 ? If no, whether it is otherwise a mineral within the meaning of the said Act? These are the two significant questions which emerge at the very threshold in this set of four closely connected writ petitions before this Full Bench. The reference has been necessitated by a frontal challenge to the correctness of the recent Division Bench judgment in Keshri Mai Jain V/s. State of Bihar, AIR 1985 Pat 114.

2. Learned counsel for the parties are agreed that the facts herein are similar and the issues of law virtually identical. The matrix of relevant facts giving rise to the pristinely legal questions aforesaid may be noticed with brevity from C.W.J.C. 472 of 1985(R) (The Tata Iron and Steel Company Limited and another V/s. State of Bihar) despite the large volume of pleadings on the record.

3. The 1st petitioner-Messrs Tata Iron and Steel Company Limited - owns and is possessed of various captive mines in the districts of Hazaribagh and Dhanbad meant primarily for th