RT Journal Article SR Electronic T1 Mineralogical notes JF American Journal of Science JO Am J Sci FD American Journal of Science SP 249 OP 251 DO 10.2475/ajs.s3-29.171.249 VO s3-29 IS 171 A1 William Earl Hidden YR 1885 UL http://www.ajsonline.org/content/s3-29/171/249.abstract AB