Abstract: Electron micrographs of 7 Å-type and 10 Å-type garnierites have been recorded at 5·104–105X magnifications to show the morphological character of these minerals, and at 106X magnification to show structural features of the particles. The 7 Å, serpentine-like minerals show a greater variety of morphological forms including tube- and rod-shaped particles and also platy forms and poorly defined, fluffy particles, probably aggregates. The 10 Å, talc-like minerals show mainly platy forms and fluffy aggregates, and generally very few tube or rod-shaped particles. At 106X magnifications, the 7 and 10 Å layer spacings are seen directly. In the samples examined, the 7 Å spacings are more clearly and more regularly defined than the 10 Å spacings.