Alkaline Rocks and Carbonatites of the World

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Occurrence number: 
Longitude: 32.33, Latitude: -25.75

Nepheline syenite forms a hill of about 1.5x0.3 km close to the Chambandjouve River approximately 8 km south-southwest of Pessene. The rock contains abundant orthoclase crystals up to a centimetre in length and fewer 2-3 mm phenocrysts of nepheline and zoned aegirine-augite in a groundmass of the same minerals and accessory titanite, zeolite and calcite. Xenoliths in the nepheline syenite are mineralogically similar but may contain biotite and/or a brown amphibole. A rock analysis is given by Young (1920)

YOUNG, R.B. 1920. The rocks of a portion of Portuguese East Africa. Transactions of the Geological Society of South Africa, 23: 98-113.
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith