Quartz
Quartz is the most abundant mineral on Earth's continental crust and one of the most recognizable minerals for rockhounds. Its six-sided prismatic crystals with pointed terminations are instantly recognizable. Found in virtually every geological environment, quartz comes in more varieties than almost any other mineral.
Physical Properties
Chemical Formula
SiO₂
Hardness (Mohs)
7
Color
Colorless, white, purple, pink, smoky brown, yellow
Luster
Vitreous (glassy)
Crystal System
Hexagonal (trigonal)
Streak
White
Cleavage
None (conchoidal fracture)
Specific Gravity
2.65
🔍 Field Identification Tips
Look for six-sided crystals, glassy luster, and a hardness of 7 (scratches a steel knife easily). Quartz has no cleavage — it breaks with a curved (conchoidal) fracture like glass. The crystal faces often show horizontal striations.
Varieties & Forms
📍 Where to Find Quartz in the US
Uses & Applications
Electronics (oscillators, microchips), glass manufacturing, jewelry, gemstones, watches, abrasives.
💰 Collector Value Guide
Clear quartz: $1–$10/lb. Arkansas clusters: $5–$500 depending on quality. Premium specimens can fetch thousands.
Find Quartz With Our Tools
Use the We Lick Rocks app to identify specimens, find dig sites, and connect with local rockhounds.