Which one of the following statements about metamorphic rocks is not correct?

Metamorphism involves the recrystallisation and reorganisation of minerals under pressure and temperature changes [1]. Foliation or lineation occurs when minerals arrange into layers or lines [1]. Statement 1 is correct as minerals often segregate into wavy bands or platy surfaces during this process [1]. Statement 2 is correct because broad mineral banding, typical of gneiss, results in extremely hard, resistant rocks . Statement 3 is correct as thin foliations, such as those in schist, allow the rock to flake apart easily [1]. Statement 4 is incorrect because rocks composed of a single dominant mineral, like limestone or pure sandstone, typically form non-foliated metamorphic rocks like marble or quartzite [1]. These monomineralic rocks lack the variety of minerals necessary to segregate into distinct layers or bands, resulting in a granoblastic texture rather than a foliated one.

Sources

1. [1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 13: Types of Rocks & Rock Cycle > 13.3. Metamorphic Rocks > p. 173