RT Journal Article SR Electronic T1 On an azure-blue pyroxenic rock from the middle Gila, New Mexico JF American Journal of Science JO Am J Sci FD American Journal of Science SP 279 OP 280 DO 10.2475/ajs.s3-43.256.279 VO s3-43 IS 256 A1 George Perkins Merrill A1 R. L. Packard YR 1892 UL http://www.ajsonline.org/content/s3-43/256/279.abstract AB