RT Journal Article SR Electronic T1 Mineralogical notices JF American Journal of Science JO Am J Sci FD American Journal of Science SP 246 OP 248 DO 10.2475/ajs.s2-41.122.246 VO s2-41 IS 122 A1 Brush, George Jarvis YR 1866 UL http://www.ajsonline.org/content/s2-41/122/246.abstract AB