Abstract
DURING recent petrological research on volcanic rocks collected by the Royal Society Tristan da Cunha Expedition1, many specimens of varying composition have been found to contain leucite. The mineral occurs interstitially, is weakly birefringent with a high negative relief, and displays poorly denned lamellar and cross-hatched twinning. The refractive index, determined in sodium light by the immersion method, is 1.507 ± 0.003. Although similar to analcime in thin section, the refractive index is much higher (analcime, n= 1.487) even allowing for the possibility of desilication2 or the substitution of potassium for sodium ions3. Identification of the mineral as leucite was confirmed by the Department of Mineralogy, British Museum (Natural History), with four X-ray powder photographs (Nos. 9652, 9845, 9846 and 9847) on material picked from three rock crushes.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Gass, I. G., et al., Nature, 194, 1119 (1962).
Saha, P., Amer. Min., 44, 303 (1959).
Larsen, E. S., and Buie, B. F., Amer. Min., 23, 838 (1938).
Lacroix, A., C.R. Acad. Sci., Paris, 192, 1161 (1931).
Edwards, A. B., B.A.N.Z. Antarc. Research Exp. 1929–1931, Ser. A, 2, 5 (1938).
Holmes, A., and Harwood, H. F., Uganda Geol. Surv. Mem., 3 (1937).
Larsen, E. S., et al., Bull. Geol. Soc. Amer., 52, 1733 (1941).
Wade, A., and Prider, R. T., Quart. J. Geol. Soc., London, 96, 39 (1940).
Rittmann, A., Z. Vulkan., 15, 8 (1933).
Part, G. M., Bull. Brit. Mus. (Nat. Hist.) (Min.), 1 (1950).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
LE MAITRE, R., GASS, I. Occurrence of Leucite in Volcanic Rocks from Tristan da Cunha. Nature 198, 779–780 (1963). https://doi.org/10.1038/198779a0
Issue Date:
DOI: https://doi.org/10.1038/198779a0
This article is cited by
-
Origin and diagenesis of the Roque Nublo breccia, Gran Canaria (Canary Islands) — Petrology of roque nublo volcanics, II
Bulletin Volcanologique (1980)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.