KIMBERLITES OF ZIMBABWE: ABUNDANCE AND COMPOSITION
A.D. Khar'kiv, E.F. Roman'ko, and B.M. Zubarev
Central Research Geological Prospecting Institute of Nonferrous and Noble Metals,
129B Varshavskoe shosse, Moscow, 113545, Russia
Keywords: Kimberlites, composition, diamond association, Zimbabwe
Pages: 317-327
Subsection: PETROLOGY, GEOCHEMISTRY, AND MINERALOGY
Abstract
The composition of kimberlites from the Chingwisi, QK1, and QK2 pipes is considered, and new data on a single operating pipe, River Ranch, are reported. Original calcretized kimberlites of the upper horizons of the Chingwisi pipe are described. Garnets of ultrabasic paragenesis of diamond association are extremely scarce and pyrope-almandine garnets of eclogite paragenesis of the same association are abundant in QK1 and QK2. These garnets can serve as indicators in search for diamond pipes with the use of the heavy-concentrate-mineralogical method. Kimberlite bodies of mobile belts can differ in composition from those of Archean cratons.
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