The Manhattan schist is a formation of micaschist rock that underlies much of the island of Manhattan in New York City. It is well suited for the foundations of tall buildings and the two large concentrations of skyscrapers on the island occur where the formation is close to the surface. Image File history File links Download high resolution version (1701x1845, 997 KB) Manhattan schist Manhattan Schist from Southeastern New York state, USA. Photo taken by myself on 3-13-05. ... Image File history File links Download high resolution version (1701x1845, 997 KB) Manhattan schist Manhattan Schist from Southeastern New York state, USA. Photo taken by myself on 3-13-05. ... rock with mica Mica sheet mica flakes The mica group of minerals includes several closely related materials having highly perfect basal cleavage. ... Schist The schists form a group of medium-grade metamorphic rocks, chiefly notable for the preponderance of lamellar minerals such as micas, chlorite, talc, hornblende, graphite, and others. ... The Borough of Manhattan, highlighted in yellow, lies between the East River and the Hudson River. ... Flag Seal Nickname: Big Apple Location Location in the state of New York Government Counties (Boroughs) Bronx (The Bronx) New York (Manhattan) Queens (Queens) Kings (Brooklyn) Richmond (Staten Island) Mayor Michael Bloomberg (R) Geographical characteristics Area City 1,214. ...