RT Journal Article SR Electronic T1 Brookite from Magnet Cove, Arkansas JF American Journal of Science JO Am J Sci FD American Journal of Science SP 387 OP 389 DO 10.2475/ajs.s3-31.185.387 VO s3-31 IS 185 A1 Samuel Lewis Penfield YR 1886 UL http://www.ajsonline.org/content/s3-31/185/387.abstract AB