Summary: Nepheline in a basic syenite from the Marangudzi complex is relatively Ca-rich with CaO from 1·9 to 2·4 (wt) %. This Ca-rich nepheline sometimes occurs in intimate intergrowths with plagioclase (andesine). These intergrowths are thought to have formed at temperatures in the order of 750°–850°C by resorption of plagioclase with simultaneous replacement by nepheline.
Mineralogical Magazine; June 1972 v. 38; no. 298; p. 670-677; DOI: 10.1180/minmag.1972.038.298.03
© 1972, The Mineralogical Society
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