Quartz

Hardness: 7 on Mohs scale, Color: Clear, white, gray, or pale pink, Luster: Vitreous (glassy), Crystal Structure: Trigonal, Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Forms in a wide variety of geological environments, including igneous, metamorphic, and sedimentary rocks. Often crystallizes from silica-rich hydrothermal veins and pegmatites.

Used in electronics, watchmaking, glass manufacture, abrasive materials, and as gemstones or ornamental mineral specimens.

Quartz is one of the most abundant and widely distributed minerals on Earth's continental crust. Due to its piezoelectric properties, it is extensively used in electronic devices to generate precise frequency signals.

Easily identified by its hardness (scratches glass), lack of cleavage, and vitreous luster. Found worldwide in nearly every type of geological terrain.