greenschist

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Both the sensory and the motor cortices of the right cerebral portion of the brain contain a sequence of points known as the “homunculus” which corresponds to points in the body (see Exhibit 1, next page).

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Shuksan Greenschist
Fine-grained thinly foliated greenschist and black phyllite occur in a north-northwest-trending belt along the west edge of the area. The rocks are particularly conspicuous near Bacon Peak and in the vicinity of Mount Shuksan.
The mountain is composed of Shuksan greenschist, oceanic basalt that was metamorphosed when the Easton terrane collided with the west coast of North America, approximately 120 million years ago. The mountain is an eroded remnant of a thrust plate formed by the Easton collision.

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metamorphic
rock
geology

Wikipedia

Greenschist (Wikipedia) Greenschists are metamorphic rocks that formed under the lowest temperatures and pressures usually produced by regional metamorphism, typically 300–450 °C (570–840 °F) and 2–10 kilobars (29,000–145,000 psi). Greenschists commonly have an abundance of green minerals such as chlorite, serpentine, and epidote, and platy minerals such as muscovite and platy serpentine. The platiness gives the rock schistosity (a tendency to split into layers). Other common minerals include quartz, orthoclase, talc, carbonate minerals and amphibole (actinolite).