Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-24T01:37:32.558Z Has data issue: false hasContentIssue false

An Association of Anthophyllite and Enstatite

Published online by Cambridge University Press:  01 May 2009

F. Coles Phillips
Affiliation:
Fellow of Corpus Christi College, Cambridge.

Extract

Of the naturally occurring forms of (Mg, Fe) SiO3, only two are of any great petrological importance. Rhombic pyroxenes of the enstatite-hypersthene series are common in many igneous rocks and in the metamorphic derivatives of these and of sediments. Members of the anthophyllite group of rhombic amphiboles are of much more restricted occurrence, being practically confined to crystalline schists and metasomatic products. The stability relationships of these forms and of the rarer monoclinic clinoenstatite and kupfferite were originally investigated by Allen, Wright, and Clement. Enstatite was obtained by crystallizing a glass below 1100° C., and anthophyllite by very rapid cooling from a melt at about 1600° C. Some uncertainty still exists, but it is clear that at least under normal pressure clinoenstatite is the only stable form.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 1930

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

page 514 note 1 It seems desirable to apply the name kupfferite to the monoclinic form of amphibole, the end-member of the cummingtonite series, in accordance with the original usage by Kokscharow, and that followed by Hintze, Dana-Ford and others. The Carnegie Institute workers apply it to the magnesian end-member of the anthophyllite series.

page 514 note 2 A.J.S., 4, xxii, 1906 385438.Google Scholar

page 514 note 3 Eitel, W., Wissenschaft. Forschungsber., Naturwiss. Reihe, 1925, xiii, 44Google Scholar; Phys. Chem. der Silikate, Leipzig, 1929, 290.Google Scholar

page 514 note 4 Min. Mag., iii, 1880, 21.Google Scholar

page 514 note 5 Q.J.G.S., lxxxiii, 1927, 642–4.Google Scholar

page 514 note 6 Compt. Rend., cii, 1886, 1332.Google Scholar

page 514 note 7 Op. cit., p. 21. This analysis is given as of anthophyllite, but since slides of his own material show considerable amounts of pyroxene, it may reasonably be assumed that no separation was carried out, and that the analysis is that of an anthophyllite-pyroxene rock.

page 514 note 8 Journ. Wash. Acad. Sci., x, 1920, 413.Google Scholar

page 516 note 1 Op. cit., p. 1332.

page 516 note 2 Phillips, F. Coles, op. cit., p. 642.Google Scholar