gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1960.032.250.07 Magnetic Susceptibility of Garnet Frost M. J. B.Sc., Ph.D., F.G.S. 1 Department of Geology, University of Western Australia.

Pressent address: Department of Geology, The University of Canterbury, Christchurch, C.l, New Zealand.

 9 1960 32 250 573 576 Copyright © 1960, The Mineralogical Society 1960 Summary

The mass suseeptibility of 23 analysed or partially analysed garnets has been measured by means of a calibrated Franz Isodynamic magnetic separator. Straight lines are fitted to the adjusted data for mass susceptibility and molecular composition. The mass susceptibilities of the theoretical end-members in electromagnetic units × 106 are estimated as: almandine, 68±2 e.m.u.; spessartine, 81±3 e.m.u.; and andradite, 49±3 e.m.u. Grossular and pyrope are assumed to have susceptibilities of nil.