Quartz can be identified by combining several physical properties rather than relying on color alone. Natural quartz is silicon dioxide with a Mohs hardness of 7, a glass-like luster, no true cleavage, and a typical conchoidal fracture.

Quartz can be identified by its hardness, glass-like appearance, crystal structure, color variation, and resistance to normal scratching. In home surfaces, sinks, and decorative products, the word “quartz” may refer to natural quartz mineral, engineered quartz slabs, or quartz composite materials. These are related, but they are not exactly the same.