Here's why:
* Polymorphs are minerals that have the same chemical composition but different crystal structures.
* Quartz is primarily made up of silicon dioxide (SiO2).
* Feldspar is a group of minerals with a more complex chemical composition, typically including aluminum, silicon, oxygen, sodium, potassium, and calcium.
Therefore, quartz and feldspar have different chemical compositions, making them distinct minerals and not polymorphs.
Examples of Polymorphs:
* Diamond and Graphite are both made of pure carbon but have different crystal structures.
* Calcite and Aragonite are both calcium carbonate (CaCO3) with different crystal structures.
