Limestone is the parent rock of a non-foliated metamorphic rock called marble.

Here's why:

* Limestone: A sedimentary rock primarily composed of calcium carbonate (CaCO3).

* Metamorphism: The process of transforming existing rocks (like limestone) through heat and pressure, but without melting them completely.

* Marble: Formed when limestone undergoes metamorphism. The heat and pressure cause the calcium carbonate crystals within the limestone to recrystallize, creating a denser, more compact rock with a characteristically granular texture. Marble is often used in building materials and sculptures due to its beauty and durability.

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