| | Journal (article/letter/editorial) | 87 Helvine from a lithium pegmatite near Salisbury, Southern Rhodesia. By O. y o n KNO~I~ING, M.Sc....found in a granite pegmatite associated with microcline-perthite, petalite, spodumene, muscovite, and spessartine...examining the Casa Ventura lithium pegmatite, situated in PreCambrian rocks some 16 miles to the east of Salisbury...minerals are found within this region. The present pegmatite has the shape of an inclined lenticular sheet...surrounded by greenstone. The main body of the pegmatite consists of grey coarse microcline perthite associated | | | Book (volume) | separately as barium felspars (p. 166). In some pegmatite microclines the rare alkalies may reach major... The clear yellow crystals from a miarolitic pegmatite are of gem quality and as a consequence have often...(“cryptoperthite”), nordmarkite, Spalen, Nordmark, Oslo district, Norway (Oftedahl, 1948). Anal. Lars Lund. 3....Orthoclase microperthite (moonstone) E. Spencer. pegmatite, Ambalangoda, Ceylon (Spencer, 1937). Anal...pyroxene granulite of the charnockite senes, Salem district Madras (Howie, 1955). Anal. R. A. Howie. 16. Colourless |
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