When sandstone is subjected to intense heat and pressure, it transforms into quartzite.

Here's why:

* Sandstone's Composition: Sandstone is primarily composed of quartz grains cemented together.

* Heat and Pressure: The heat and pressure cause the quartz grains to recrystallize and interlock, creating a much denser and harder rock.

* Quartzite Formation: This process results in a metamorphic rock called quartzite, characterized by its hardness, durability, and often banded appearance.

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