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Observations on the colouring of pink and green zoned tourmaline

Published online by Cambridge University Press:  14 March 2018

J. E. S. Bradley
Affiliation:
Geology and Physics Departments, King's College, University of London
Olive Bradley
Affiliation:
Geology and Physics Departments, King's College, University of London

Extract

This investigation was concerned with two aspects of the colour-zoning in tourmaline: firstly, the origin of the green and pink colours ; secondly, the reason for the apparent incompatibility of these two forms. Much of the previous work on the colour of tourmaline has involved the use of emission spectra. This method provides information as to which elements are present; it does not, of course, indicate which of the twenty or so elements identified is responsible for the colour, although it may be possible to infer this. Absorption spectra, on the other hand, are directly concerned with colour. They have been employed quite extensively in Germany, and more recently in Russia, but the earlier data and instruments were often inadequate. The last decade has seen marked improvements in the technique of absorption spectroscopy, particularly in the development of photo-electric methods for the quantitative recording of spectra, and the method is likely to prove one of increasing value.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1953

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References

page 26 note 1. Carobbi, G. and Pieruccini, R., Spectrographic analyses of tourmalines from the island of Elba with correlation of color and composition. Amer. Min., 1947, vol. 32, pp. 121130. [M.A. 10-317.]Google Scholar

page 26 note 2. Mateos, J. p., El color en la tourmalina. Noms y Comunic. Inst. Geol. y Minero de España, 1944, no. 13, pp. 217289. [M.A. 9-198.]Google Scholar

page 26 note 3. Warner, T. W., Spectrographic analysis of tourmaline with correlation of color and composition. Amer. Min., 1935, vol. 20, pp. 531536. [M.A. 6-266.]Google Scholar

page 26 note 4. Kolbe, E., Über die Färbung yon Mineralien dureh Mangan, Chrome und Eisen. Neues Jahrb. Min., Abt. A, 1935, Beil.-Bd. 69, pp. 183254. [M.A. 7-135.]Google Scholar

page 26 note 5. ISange, B. and Eitel, W., Über eine Methode zur Untersuchung der Absorption.... Tschermaks Min. Petr. Mitt., 1931, vol. 41, pp. 435452. [M.A. 5-122.]Google Scholar

page 26 note 6. Melankholin, N. M., On the colouring of magnesial-ferruginous mica. Trav. Lab. Crist. Aead. Sci. URSS, 1940, no. 2, pp. 6172. [M.A. 9-197.]Google Scholar

page 26 note 7. Grum-Grzhimailo, S. V., On the colouring of minerals caused by chrome. Trav. Lab. Crist. Aead. Sci. URSS, 1940, no. 2, pp. 7386. [M.A. 9-190.]Google Scholar

page 27 note 1. Johns, R. and Wright, L. A., Gem and lithium-hearing pegmatites of the Pala district, San Diego County, California. Special Rep. Division Mines, California, 1951, no. 7-A, 72 pp. [M.A. 11487.]Google Scholar

page 28 note 1. D = optical density = logl0 (incident intensity/(transmitted intensity).

page 31 note 1. F. Machatschki, Notiz über die Entwässerung des Turmalins. Zentralblatt Min., Abt. A, 1941, pp. 135-137. [M.A. 8-382.]

page 32 note 1. Hamburger, G. E. and Buerger, M. J., The structure of tourmaline. Amer. Min., 1948, vol. 33, pp. 532540. [M.A. 10-541.]Google Scholar

page 32 note 2. Ito, T. and Sadanaga, R., A Fourier analysis of the structure of tourmaline. Acta Cryst., 1951, vol. 4, pp. 385390. [M.A. 11-429.]CrossRefGoogle Scholar

page 33 note 1. Agafonova, T. N., Chemical composition and colour of tourmalines from the Borshehovochnoi Mts. Compt. Rend. (Doklady) Acad. Sci. URSS, 1947, vol. 55, pp. 849852. [M.A. 10-317.]Google Scholar

page 33 note 2. E. S. Dana, System of Mineralogy, 6th edit., 1892, p. 555.

page 33 note 3. Kunitz, W., Die Mischungsreihen in der Turmalingruppe . . . . Chemie der Erde, 1929, vol. 4, pp. 208251. [M.A. 4-203.]Google Scholar

page 37 note 1. Quensel, P. and Gabrielson, O., Minerals of the Varuträsk pegmatite. XIV. The tourmaline group. Geol. För. Förh. Stockholm, 1939, vol. 61, pp. 6390. [M.A. 7-335.]Google Scholar