Charnockite

This combination is generated only deep in the crust by tectonic forces that operate on a grand scale, so granofels is a product of regional, rather than contact, metamorphism.

It was named by geologist T. H. Holland in 1893 after the tombstone of Job Charnock, in St John's Church in Kolkata, India, which is made of this rock.

[2][3] The charnockite series includes rocks of many different types, some being felsic and rich in quartz and microcline, others mafic and full of pyroxene and olivine, while there are also intermediate varieties corresponding mineralogically to norites, quartz-norites and diorites.

A special feature, recurring in many members of the group, is the presence of a strongly pleochroic, reddish or green orthopyroxene (ferroan enstatite formerly known as hypersthene).

Rocks of the charnockite series may be named by adding orthopyroxene to the normal igneous nomenclature (e.g. orthopyroxene-granite), but specific names are in widespread use such as norite, mangerite, enderbite, jotunite, farsundite, opdalite and charnockite (in the strict sense); equivalents of gabbro, monzonite, tonalite, monzodiorite, monzogranite, granodiorite and granite.

The reflection of light from the surfaces of these inclusions gives the minerals often a peculiar appearance, e.g. the quartz is blue and opalescent, the feldspar has a milky shimmer like moonshine, the hypersthene has a bronzy metalloidal gleam.