Here's why:

* Limestone is a sedimentary rock primarily composed of calcium carbonate (CaCO3).

* Quartz is a common mineral found in many rocks, including limestone.

* Recrystallization is a process where existing minerals in a rock change their size, shape, or arrangement under heat and pressure.

When limestone undergoes recrystallization, the calcium carbonate crystals become larger and more tightly packed, forming marble. This process typically happens due to metamorphism, where heat and pressure transform the existing rock.

Therefore, marble is the result of recrystallized limestone, often containing quartz and other minerals that were present in the original limestone.