Beryllium minerals in Cornwall and Devon: helvine, genthelvite, and danalite
- 1 December 1961
- journal article
- Published by Mineralogical Society in Mineralogical Magazine and Journal of the Mineralogical Society
- Vol. 32 (255) , 921-940
- https://doi.org/10.1180/minmag.1961.032.255.01
Abstract
Summary Helvine and genthelvite are recorded for the first time in Britain; of the former, three occurrences in Cornwall and one in Devon, and of the latter, one occurrence in Cornwall, are described. British danalite has hitherto been represented by two old specimens with the vague locality ‘Redruth’, Cornwall; occurrences at four Cornish localities are described, and a further Cornish locality is provided by two old specimens previously labelled as garnet. Partial chemical analyses for the helvine, genthelvite, and danalite specimens are presented; helvine and genthelvite occur in pyrometasomatic-hydrothermal deposits in metamorphosed calcareous sediments and, in one instance, in greenstone; danalite in hydrothermal deposits or lodes in metamorphosed greenstone; the parageneses of the three minerals are discussed.Keywords
This publication has 8 references indexed in Scilit:
- The rediscovery of churchite in CornwallMineralogical Magazine and Journal of the Mineralogical Society, 1956
- The geochemistry and mineralogy of rock weathering (1) the Lizard area, CornwallGeochimica et Cosmochimica Acta, 1953
- On rhodonite and tephroite from Treburland manganese mine, Altarnun, Cornwall; and on rhodonite from other localities in Cornwall and DevonshireMineralogical Magazine and Journal of the Mineralogical Society, 1946
- Simple tests for the detection of the beryllium mineral helvite [New Mex.]Economic Geology, 1944
- Note on an occurrence of bertrandite and beryl at the South Crofty mine, Cornwall (With Plate XXV.)Mineralogical Magazine and Journal of the Mineralogical Society, 1940
- On the occurrence of Phenacite and Scheelite at Wheal Cock, St. Just, CornwallMineralogical Magazine and Journal of the Mineralogical Society, 1920
- On the occurrence of metamorphic minerals in calcareous rocks in the Bodmin and Camelford areas, CornwallMineralogical Magazine and Journal of the Mineralogical Society, 1908
- Danalite from CornwallMineralogical Magazine and Journal of the Mineralogical Society, 1892