haplite

from The Century Dictionary.

• noun A crystalline-granular mixture of quartz and orthoclase.
• noun Haplite proper is a granite free, or nearly free, from muscovite or any dark silicate. The name is also applied by Rosenbusch and other petrographers to the highly feldspathic members of the syenite, monzonite, and diorite families, such rocks being usually called syenite-haplite, diorite-haplite, etc. This extension of the term is connected with the belief that such haplitic rocks are differentiation products of syenitic, monzonitic, or dioritic magmas. The rocks in question often occur in dikes and possess the panautomorphic granular texture, and these features enter into the definitions given by Rosenbusch.