Abstract
Since the publication of the paper on the minerals of the montmorillonite group by Ross and Hendricks (1945) some species have been added to the group, and minor changes in the acceptable species have become advisable. No radical changes are proposed, but a review of the members and their grouping will be presented. The acceptable dioctahedral members of the group appear to be montmorillonite, nontronite and volchonskoite. Beidellite should be discontinued. The acceptable trioetahedral members of the group appear to include saponite, hectorite, sauconite, stevensite and medmontite. Griffithite is probably a useful term for an iron-rich saponite. Representative chemical analyses and formulas have been assembled to illustrate relationships.
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Chukhrov, F. V. and Anosov, F. Ya. (1950) Medmontite, a copper bearing mineral of the montmorillonite group: Vses. Mineralog. Obshch. Zapiski, ser. 2, v. 79, no. 1, pp. 23–27. (In Russian.)
Dimitrov, Strashimir (1942) Chromhaltige Tonminerale und Nickel-Asbolan in der Umgebung von Nevrokop: Ann. Univ. Sofia, II. Fac. Phys-Math., Livre 3, Sci. Nat., v. 38 (for 1941-42), pt. 3, pp. 207–224 (In Bulgarian), pp. 225–226 (German summary); (1948) Min. Abstr., v. 10, p. 300.
Faust, G. T. (1955) Thermal analysis and x-ray studies of griffithite: J. Wash. Acad. Sci., v. 45, pp. 66–70.
Faust, G. T. and Murata, K. J. (1953) Stevensite, redefined as a member of the montmorillonite group: Amer. Min., v. 38, pp. 973–987.
Foster, M. D. (1951) The importance of exchangeable magnesium and cation-exchange capacity in the study of montmorillonitic clays: Amer. Min., v. 36, pp. 717–730.
Foster, M. D. (1953) Geochemical studies of clay minerals. III. /The determination of free silica and free alumina in montmorillonites: Geochim. Cosmochim. Acta, v. 3, pp. 143–154.
Foster, M. D. (1954) The relation between “illite,” montmorillonite, and beidellite: in Clays and Clay Minerals, Natl. Acad. Science—Natl. Research Council, pub. 327, pp. 386–397.
Genth, F. A. (1875) Preliminary report on the mineralogy of Pennsylvania: Pennsylvania Geol. Survey, 2d, B, pp. 1–206.
Grim, R. E. and Rowland, R. A. (1942) Differential thermal analysis of clay minerals and other hydrous materials. II: Amer. Min., v. 27, pp. 801–818.
Larsen, E. S. and Steiger, G. (1928) Dehydration and optical studies of alunogen, nontronite, and griffithite: Amer. J. Sci., ser. 5, v. 15, pp. 1–19.
Palache, Charles and Vassar, H. E. (1925) Some minerals of the Keweenawan copper deposits; pumpellyite, a new mineral; sericite; saponite: Amer. Min., v. 10, pp. 412–418.
Ross, C. S. (1946) Sauconite—a clay mineral of the montmorillonite group: Amer. Min., v. 31, pp. 411–424.
Ross, C. S. and Hendricks, S. B. (1945) Minerals of the montmorillonite group, their origin and relation to soils and clays: U.S. Oeol. Survey, Prof. Paper 205-B, pp. 23–79.
Roy, Rustum and Sand, L. B. (1956) A note on some properties of synthetic montmorillonites: Amer. Min., v. 41, pp. 505–509.
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Ross, C.S. Eeview of the Relationships in the Montmorillonite Group of Clay Minerals. Clays Clay Miner. 7, 225–229 (1958). https://doi.org/10.1346/CCMN.1958.0070114
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DOI: https://doi.org/10.1346/CCMN.1958.0070114