The Water Content of Nepheline


Anton Beran & George R. Rossman

Division of Geological and Planetary Sciences
California Institute of Technology, Pasadena, California,



The water content of nephelines from various localities were studied through thermal weight loss and single-crystal infrared specroscopy. Typical water contents in nepheline are on the order of 0.2 to 0.5 wt.%. The H2O molecule exists in multiple crystallographic orientations, presumably in the potassium site. Two orientations of water are indicated in ther spectrum of nepheline from Monte Somma. When the crystal is heated to 350ºC, a third orientation develops.


The infrared spectrum of nepheline from Mt Somma, Italy, after heating to, and cooling from, the indicated temperatures

Mineralogy and Petrology 40, 235-240.