Clay veins
Subtitle: their occurrence, characteristics, and support
By: by Frank E. Chase and James P. Ulery.
Contributors: Ulery, J. P.
Series: Report of investigations / United States Department of the Interior, Bureau of Mines ;; 9060; Report of investigations (United States. Bureau of Mines) ;; 9060.
Publisher: U.S. Dept. of the Interior, Bureau of Mines
Published: 1987
Place of publication: PGH., PA
Language: eng
Number of pages: 19
Subjects: Ground control (Mining); Clay veins.; Coal mines and mining -- Safety measures.
Notes: Bibliography: p. 18-19.