Rhyolite Rock

rhyolite host rock with garnet

Rhyolites are extrusive igneous rocks with very high silica content. It’s usually gray or pink, with tiny grains that are difficult to observe without magnification or a 10x-powered loop. Rhyolite is composed of Plagioclase, Quartz, and Sandine, with minor amounts of Biotite and Hornblende. If you’ve dug for rocks and minerals then you’ve come across […]

Galena Mineral

galena crystals

Galena is relatively easy to identify because of its distinct silver color (metallic luster) and crystal structure. Freshly broken pieces will exhibit a perfect cleavage in three directions intersecting at 90 degrees. If you have a specimen then you’ll need to understand that it will tarnish over time to a dull gray. Whatever you do, […]