gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1967.036.277.12 A Reinterpretation of Monalbite Brown William L. 1 Department of Geology, The University, Manchester 13

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 3 1967 36 277 80 82 11 7 1966 Copyright © 1967, The Mineralogical Society 1967 Summary

A neutron activation analysis of one of the crystals of ‘monalbite’, which was monoclinic at room temperature, shows that it contains a large proportion of potassium. It is thus not a polymorph of pure NaAlSi3O8. The contamination occurred by transfer of K through the atmosphere of the furnace from potassium-bearing ceramic materials.