gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1960.032.248.02 Electron-Optical Data for Crystals of Scarbroite1 Brindley G. W. M.Sc., Ph.D. Comer J. J. M.S. The Pennsylvania State University, University Park, Pennsylvania.

Contribution No. 59-21 from the college of Mineral Industries, The Pennsylvania State University, University Park, Pa.

 3 1960 32 248 363 365 Copyright © 1960, The Mineralogical Society 1960 Summary

Electron micrographs of scarbroite show thin platy crystals of about 1 μ size, having rhombic outlines with angles 66° ± 1° and 113° ± 1°. Single-crystal electron-diffraction patterns show rectangular net patterns, with d100 = 9·90 Å., d010 = 14·67 Å., γ* = 90° ± 0·05°. Strong hk0 reflections show a pseudohexagonal arrangement, but true symmetry is probably orthorhombic or monoclinic. Faces outlining rhombic forms are of type {11l}, {1¯1l}.