Diamond drilling and diamond bit investigation.

Additional Authors:	Obert, Leonard,, Agnew, Wing G., Long, Albert., Chayes, Felix., Gabriel, Alton.
Year:	1947
Document Type:	BMRA
Issuing Agency:	U.S. Dept. of the Interior, Bureau of Mines,
SUDOC:	I 28.23:4041
Series:	Report of investigations / United States Department of the Interior, Bureau of Mines ;
Report Number:	4041, 4233
Subjects:	Boring
	Granite
	Diamond bits--Testing
Link:	https://hdl.handle.net/2027/mdp.39015078496836