SURFACE-MORPHOLOGY OF IRON DENDRITES IN THE YANZHUANG H6 METEORITE

In the Yanzhuang H6 meteorite are small (10 mu m to 7mm) Fe-Ni dendrit es in pockets and veins. We have characterized the surface morphology of several of the dendrites by using scanning electron microscopy (wit h X-ray microanalysis). The dendrite surface has a network of growth l edges. At the edge of the apexes of the dendrites, there are four conc entric ''rings'' which are consistent with a [111] dendrite growth dir ection to produce four ring patterns parallel to the {100} planes. The Fe dendrites are partially coated with a material containing growth l edges which is rich in Fe and S, and is presumed to be FeS (troilite).