Every area of the world offers its own unique treasures for people who enjoy rockhounding. Different places exhibit different minerals, so every trip is a new adventure in discovery. Even so, some minerals are more abundant than others. Here are just five rocks that rockhounds are very likely to encounter in their search.
1. Quartzite
Quartzite is a white, tan, yellowish, pink, or gray metamorphic stone formed from when quartz sandstone is placed under high temperature and pressure. This causes the individual grains of sand and the material between them to recrystallize, forming a smooth stone with streaks of inclusions.
2. Scoria
Scoria is a type of basalt, an igneous rock formed by volcanic activity. It is dark in color, often red, brown, gray, or purplish, and has a pitted appearance similar to pumice. Unlike pumice, scoria sinks when placed in water.
3. Slate
Slate is a metamorphic rock, formed by fine-grained sand compressed under extreme pressure. It is gray, with a smooth, dull appearance (sometimes with fossils) and a tendency to break into flat sheets. In the past, slate was a writing surface. Today, it’s commonly used for roofing or flooring material.
4. Mudstone
Mudstone is made of mud hardened over time. It is possibly the most common rock found while rockhounding. It is made up of very fine, silt-like particles and looks like hardened clay. With enough pressure over time, it may become shale. Like slate, mudstone may contain fossils.
5. Granite
Perhaps best known for its use in countertops, granite has been a building material for thousands of years. It is an igneous rock, but it exhibits visible crystals and lacks scoria’s pitted appearance. Granite forms when silica-rick magma cools slowly, which forms large, interlocking crystals. Granite may be white, black, tan, pink, blue, green, gray, or red.
While every enthusiast hopes to encounter rare specimens on a rockhounding trip, even common rocks have a beauty of their own. They often exhibit unique formations, colors, or even inclusions of rarer minerals or fossils, and shouldn’t be overlooked by any rockhound.
Featured Image from Oliver Paaske/Unsplash
