Quartz

Hardness: 7 on Mohs scale. Color: Clear, colorless. Luster: Vitreous (glassy). Crystal Structure: Hexagonal (trigonal), often in prismatic crystals with pyramidal terminations or massive. Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Quartz forms under a wide range of temperatures and pressures in igneous, metamorphic, and sedimentary rocks. It crystallizes from silica-rich solutions, often in veins, geodes, and pegmatites. It's a fundamental component of many rock types. Geological Age: Formed throughout Earth's history, from Precambrian to present.

Industry: Crucial for electronics (oscillators, filters), optics (lenses, prisms), and abrasives. Construction: A major constituent of granite and sandstone, used as building material aggregate in concrete and mortar. Jewelry: Polished into beads (like in the image), cabochons, and faceted gemstones. Highly prized for its clarity and versatility.

Quartz is one of the most common minerals on Earth, found in a vast array of geological environments. The clear, colorless variety is known as Clear Quartz or Rock Crystal. It has been used for centuries in various cultures for decorative objects, healing practices, and spiritual purposes. Its piezoelectric properties make it valuable in electronics.

Field Identification: Distinguished by its hardness (scratches glass), conchoidal fracture, and often hexagonal crystal habit. Common Locations: Found globally, particularly in igneous rocks like granite and rhyolite, metamorphic rocks like gneiss and schist, and sedimentary rocks like sandstone. Also abundant in hydrothermal veins and alluvial deposits. Tips for Collectors: Look for well-formed crystals in vugs and geodes, or massive veins in host rock. Clear quartz is easily recognizable by its transparency.