01019cam a22002891 4500 gs 21000322 DLC 20260227111325.0 770720s1921 azu 000 0 eng c gs 21000322 (OCoLC)3128435 U.S. Geol. Survey. Library TxEU OCoLC DLC premarc TN948.F6 A4 402(274)Ar4 MN 1.3:B 85/114 azdocs Allen, Milton Arthur, 1890- . Fluorspar, by M. A. Allen and G. M. Butler. Published by the University of Arizona, Arizona Bureau of mines. Tucson, Ariz., 1921. 19 p. 23 cm. [Arizona. State bureau of mines] Bulletin no. 114. Mineral technology series, no. 25 At head of title: ... University of Arizona bulletin. Cover title. "Selected bibliography": p. 18-19. Fluorspar. Butler, G. M. (Gurdon Montague), 1881- joint author. 26113 26113