Iron crystals in lunar brecciasMany of the vugs in the highly recrystallized breccias from Apollos 14, 15, and 16 contain euhedral iron crystals. Three populations have been recognized based on crystal habit. In the first group the trapezohedron predominates and the cube faces are smaller. The second group is characterized by the cube as the dominant form; trapezohedron and tetrahexahedron faces are smaller and about equally developed. The dominant habit of the third group is the octahedron with smaller but equally developed cube and dodecahedron faces. Iron has been mobilized and redistributed in a vapor phase. The euhedral crystals, the abundant growth steps, and the open network of substrate crystals clearly support the concept of growth from a vapor-phase.
Document ID
19740040118
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Clanton, U. S.
Mckay, D. S.
Laughon, R. B. (NASA Johnson Space Center Houston, Tex., United States)
Ladle, G. H. (Lockheed Electronics Co., Inc. Houston, Tex., United States)