Porphyry

Porphyry is a type of volcanic rock characterized by large, well-formed crystals embedded in a finer-grained matrix. This texture indicates that mineral crystals grew slowly underground before the lava erupted, creating the distinctive coarse crystals surrounded by a smoother background. Porphyry is important both geologically and economically, as it often hosts valuable mineral deposits like copper, gold, and molybdenum. Its unique formation process provides insights into volcanic activity and mineralization, making it significant in studies of Earth's geology and in the mining industry.