Diamond drilling blast holes, Bell Mine, the Warner Co., Centre County, Pa.

Author:	Mosier, McHenry.
Year:	1948
Document Type:	USBI
Issuing Agency:	Dept. of the Interior, Bureau of Mines,
SUDOC:	I 28.27:7429
Series:	Information circular / United States. Bureau of Mines ;
Report Number:	7429
Subjects:	Mineral industries--Pennsylvania
	Diamond bits
Link:	https://hdl.handle.net/2027/mdp.39015077577420