Learning how to identify quartz is one of the most practical skills in geology and rock collecting. Quartz is among Earth’s most abundant minerals, found in almost every rock type and in many forms—from large crystals in geodes, to glittering druzy coatings, to fine grains in sandstone. Because its appearance varies widely, beginners often ask: “How can I tell if a rock is quartz?” or “How do I identify quartz in a hand sample?”
