UPSC Civil Services Model Paper 3

The correct answer is option 1 , i.e Phyllite.
● Metamorphic rock is a class of rocks that result from the alteration of pre-existing rocks in response to changing environmental conditions, such asvariations in temperature, pressure, and mechanical stress, and the addition or subtraction of chemical components. The pre-existing rocks maybe igneous, sedimentary, or other metamorphic rocks .
● The process of metamorphism does not melt the rocks, but instead transforms them into denser, more compact rocks.
● The metamorphosed form of various igneous, sedimentary and metamorphic rocks are mentioned below:
◦ Metamorphosed forms of igneous rocks are gneiss, schist, amphibolites .
◦ Metamorphosed forms of sedimentary rocks are slate, marble, quartzite .
◦ Metamorphosed forms of metamorphic rocks are phyllite, serpentinite .
● Phyllite is a type of foliated metamorphic rock created from slate that is further metamorphosed (metamorphosed form of slate) so that very fine grained white mica achieves a preferred orientation.
● It is primarily composed of quartz, sericite mica, and chlorite.