Final answer:
Quartz is the hardest mineral listed, with a Mohs hardness of 7, compared to calcite's 3, fluorite's 4, and talc's 1.
Step-by-step explanation:
The student is asking about the relative hardness of different minerals, which is typically measured on the Mohs scale of mineral hardness. Quartz is known for being one of the most common minerals in the Earth's crust and is renowned for its hardness. On the Mohs scale, quartz ranks at a 7, which makes it the hardest mineral among the options given: calcite, fluorite, and talc rank much lower on the scale.
Calcite, which is a crystalline form of calcium carbonate (CaCO3), has a Mohs hardness of about 3, while fluorite (calcium fluoride) has a hardness of 4. Talc, on the other hand, is known to be the softest mineral on the Mohs scale, with a hardness ranking of 1. Therefore, between quartz, calcite, talc, and fluorite, quartz is the hardest common mineral.