RT Journal Article SR Electronic T1 Mineral notices JF American Journal of Science JO Am J Sci FD American Journal of Science SP 246 OP 248 DO 10.2475/ajs.s2-42.125.246 VO s2-42 IS 125 A1 Charles Upham Shepard YR 1866 UL http://www.ajsonline.org/content/s2-42/125/246.abstract AB