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7473756 
Journal Article 
A review of the mineralogy of lamproites 
Mitchell, RH 
1985 
88 
411-437 
English 
A new definition of lamproites and a revised nomenclature are presented. The new terminology, based upon a modal-textural scheme, recognizes two broad groups of lamproites: 1) phlogopite-sanidine-leucite-diopside lamproites (wyomingites, orendites, fitzroyites, cedricites, verites, etc.) characterized by the occurrence of resorbed phenocrystal phlogopite; 2) madupitic lamproites (madupite, jumillite, wolgidite) characterized by the presence of poikilitic phlogopites. The paragenesis and composition of titanian phlogopite, titanian tetraferriphlogopite, titanian potassian richterite, titanian potassian arfvedsonite, diopside, enstatite, forsteritic olivine, leucite, analcite, sanidine, spinels, priderite, jeppeite, armalcolite, ilmenite, anatase, wadeite, schcherbakovite, perovskite and apatite are discussed. It is concluded that different lamproite provinces appear to be characterized by phlogopites, amphiboles, sanidines, leucites and priderites of distinctly different compositions. Phlogopites, spinels and amphiboles exhibit sufficient compositional variation for assessing the relative degree of evolution of lamproitic rocks within and between provinces. Thus on a mineralogical basis madupitic lamproites (madupite, jumillite) are more evolved than phenocrystal phlogopite and leucite lamproites (orendite, verite). (Author's abstract)-C.N. 
MINERALOGY; PETROLOGY; LAMPROITES; POTASSIC ROCKS; DIAMOND DEPOSITS