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Two new pyroxenes included in the system clinoenstatite, clinoferrosilite, diopside, and hedenbergite

Published online by Cambridge University Press:  14 March 2018

W. A. Deer  and
L. R. Wager
W. A. Deer
Affiliation:
Department of Geology, University of Manchester
L. R. Wager
Affiliation:
Department of Geology, University of Reading
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Extract

Two monoclinic pyroxenes from the Skaergaard Halvoen intrusion, Kangerdlugssuak, East Greenland, have been separated and analysed. They occur in a strongly differentiated gabbro complex which ranges from a hypersthene-olivine-gabbro at the base to a fayalite-quartz-gabbro of unique composition at the top. The differentiation has proceeded with a steady increase in iron and a corresponding decrease in magnesia, while the other major oxides remain relatively constant throughout. The clinopyroxenes in the lower horizons are in equilibrium with labradorite, normal olivine and hypersthene, and are fairly normal varieties as shown by the following optical properties:—

  1. (1) … α 1·672, β 1·678, γ 1·701, 2V 42°, γ: c 39°, sp. gr. 3·34.

  2. (2) … α 1·695, β 1·702, γ 1·722, 2V 43°, γ: c 41° sp. gr. 3·38.

Type
Research Article
Information
Mineralogical magazine and journal of the Mineralogical Society , Volume 25 , Issue 160 , March 1938 , pp. 15 - 22
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1938

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References

page 15 note 1 Wager, L. R., Geological investigations in East Greenland, Part I. Meddel. om Grøland, 1934, vol. 105, no. 2, pp. 36–37.Google Scholar

page 17 note 1 Machatschki, F., Über die Formel der monoklinen Amphibole und Pyroxene. Zeits. Krist., 1929, vol. 71, pp. 219–236. [M.A. 4–202.]Google Scholar

page 17 note 2 Warren, B. E., and Biscoe, J., The crystal structure of the monoclinic pyroxenes. Zeits. Krist., 1931, vol. 80, pp. 391–401. [M.A. 5–186.]Google Scholar

page 17 note 3 Dixon, B. E., and Kennedy, W. Q., Optically uniaxial titanaugite from Aberdeenshire. Zeits. Krist., 1933, vol. 86, pp. 112–120. [M.A. 5–440.]Google Scholar

page 17 note 4 Barth, T. F. W., Pyroxen yon Hiva Oa, Marquesas-Iseln und die Formel titanhaltiger Augite. Neues Jahrb. Min., Abt. A, 1931, Beil.-Bd. 64, pp. 217–224. [M.A. 5–219.]Google Scholar

page 18 note 1 Machatschki, F., Centr. Min., Abt. A, 1930, p. 192.Google Scholar

page 18 note 2 Doelter, C., Handbuch der Mineralchemie., 1914, vol. 2, p. 559, nos. 132–137.Google Scholar

page 18 note 3 Kunitz, , Neues Jahrb. Min., Abt. A, 1936, Beil.-Bd. 70, p. 395. [M.A. 7–30.]Google Scholar

page 18 note 4 Bowen, N.L., Schairer, J.F., and Posnjak, E., The system CaO–FeO–SiO2 . Amer. Journ. Sci., 1933, set. 5, vol. 26, pp. 193–284. [M.A. 5–454.]CrossRefGoogle Scholar

page 18 note 5 Tilley, C.E., Min. Mag., 1937, vol. 24, pp. 569–572.CrossRefGoogle Scholar

page 19 note 1 Winchell, A.N., Further studies in the pyroxene group. Amer. Min., 1935, vol 20, p. 566. [M.A. 6–294.]Google Scholar

page 19 note 2 Tomita, T., Variations in optical properties, according to chemical composition, in the pyroxenes of the clinoenstatite-clinohypersthene-diopaide-hedenbergite system. Journ. Shanghai Sci. Inst., Sect. 2., 1934, vol. 1, pp. 41–58. [M.A. 6–71.]Google Scholar

page 19 note 3 Bowen, N.L., Ferrosilite as a natural mineral. Amer. Journ. Sci., 1935, ser. 5 vol. 30, pp. 481–494. [M.A. 6–260.]CrossRefGoogle Scholar