Shattuckite

Fluorapatite is the most common member of the Apatite group. Aside from mines around the world, this mineral also occurs in human teeth that are exposed to fluoride (e.g. through toothpaste). Though colorless when pure, crystals are often formed with minor impurities that give them a wide range of colors. Some particularly attractive or deeply-colored specimens may be sought after by collectors. On the industrial side of things, fluorapatite is sometimes mined as a source of phosphorus.

Perlite is a powdery or pebble-like form of volcanic glass. This lightweight mineral has made its way into many industrial processes, from plaster formation to beer filtering. Gardeners, though, will be more familiar with it as a common soil additive. White perlite grains added to soil help it stay aerated and increase drainage.

Being a relatively rare mineral, hauerite is highly prized by collectors. This mineral is found in low-temperature environments such as solfataras, fumaroles, and marine and clay salt deposit rich in sulfur. The presence of this brownish-gray mineral is, in fact, used as an indicator of sulfur deposits in the area.

Eclogite is a dense metamorphic rock that is formed at tremendous pressures and depths. The rock often sports a striking mix of colors, with green and pink being the predominant hues (caused by the minerals garnet and omphacite, respectively). This coloration can make eclogite attractive for decorative uses. Because it forms at such great depths, it is of even greater use to geologists, who study it to learn about certain aspects of plate tectonics.

Carbonatite has a marble-like appearance and is often associated with continental rifts. Though most people don’t interact with or see carbonatite on a daily basis, it has significant commercial importance. The rock may contain large quantities of various rare earth elements including titanium, copper, iron, uranium, niobium, and phosphorus. It is therefore mined in many places around the world.

Descloizite, named for a 19th century French minerologist, is a rare mineral that often sports a distinctive, glassy appearance. Crystals of descloizite may range in hue from black to brown to deep red (impressively-colored specimens like these are highly sought after). This mineral is occasionally mined for its lead or zinc.

Despite being fetching as a gem, scheelite is more commonly sought after as a hiding place for tungsten. When that element is extracted from scheelite, it is then processed into a metal alloy. Tungsten was first extracted from this mineral in 1781 by Carl Wilhelm Scheele, after whom it was subsequently named.

Since gibbsite is predominately made of aluminum, it is widely used in metal alloy production. It is found within another mineral, Bauxite, and acts as a binding agent for other minerals. It is named after George Gibbs, a world-renowned mineral collector from the US that lived during the 18th century.