Design of drill-hole grid spacings for evaluating low-grade copper deposits

Author:	Hewlett, Richard F.
Year:	1965
Document Type:	BMRA
Issuing Agency:	U.S. Dept. of the Interior, Bureau of Mines,
SUDOC:	I 28.23:6634
Series:	Report of investigations / Bureau of Mines ;
Report Number:	6634
Subjects:	Copper mines and mining
	Copper ores
	Boring
Link:	https://hdl.handle.net/2027/mdp.39015078468132