00825cam a22002411 4500 gs 60000289 DLC 20260227111409.0 790301s1960 mtub b 000 0 eng c gs 60000289 (OCoLC)4704519 U.S. Geol. Survey. Libr. TxEU OCoLC DLC TN490.N65 C7 Crowley, Frank A. Columbium-rare-earth deposits, southern Ravalli County, Montana. Butte, Montana School of Mines, 1960. iv, 47 p. maps. 28 cm. Montana. Bureau of Mines and Geology. Bulletin 18 Bibliography: p. 46-47. Niobium ores Montana Ravalli County. Rare earths Montana Ravalli County. Bulletin (Montana Bureau of Mines and Geology) ; 18. 29487 29487