Schist

This alignment and increase in mica grain size gives the rock a silky luster.

Soapstone (also known as steatite or soaprock) is a talc-schist, which is a type of metamorphic rock.

Corundum occurs as a mineral in mica schist, gneiss, and some marbles in metamorphic terranes.

Rock types in the mountains are typically granites and metamorphic schists, and some are highly sheared near to fault zones.

The rock is actually only the visible above-ground portion of a segmented ridge, the surface expression of a large igneous batholith, called the Town Mountain Granite, of middle Precambrian (1,082 ± 6 million years ago) material that intruded into earlier metamorphic schist, called the Packsaddle Schist.

Jengish Chokusu consists of low-grade black schists, volcanoclastic metasandstones, marbles, and metabasites overlain by high-grade metamorphic charnockites.

Basement rocks include the Late Precambrian or Early Palaeozoic Skelton Group metamorphic rocks, primarily the Asgard Formation, which is a medium-high-grade marble and calc schist.

The presence of metamorphic gneisses and schists lying apparently stratigraphically above sedimentary rocks of lower Paleozoic age in the Northwest Highlands had been known since the early 19th century, convincing Roderick Murchison that the change was a purely metamorphic effect and that the upper gneiss was younger than the sediments beneath.

These rocks are largely igneous in origin, mixed with metamorphosed marble, quartzite and mica schist and intruded by later basaltic dykes and granite magma.

It is composed of Cretaceous metamorphic rocks (predominantly schists and gneisses) and quartzdioritic intrusives of Tertiary age.

The kyanite quartzite and associated schist and gneiss consist of volcaniclastic sediments and volcanic rocks that have been altered by amphibolite grade metamorphism under pressure as high as 6.5 kb and temperatures as high as 600 °C.