Orthorhombic

Orthorhombic

A member of the zeolite group of minerals, this mineral was discovered in 1803 in Germany. It occurs in cavities in basalts. It was named from the Greek natron meaning "soda," in allusion to its sodium content and lithos meaning "stone."

Discovered in 1839 and named for its type locality, Danbury, Connecticut, this mineral is found in granite, metamorphosed carbonates, and evaporites. It has a similar crystal structure to topaz and can be distinguished from it by a test for boron.

This is a mineral that is part of the enstatite-ferrosilite series and is commonly regarded as a mid-way member between these two end members. It occurs in mafic igneous rocks and is named from two Greek words meaning "very" and "strong" because ( ) its hardness is greater than that of hornblende.

This mineral is usually recognized by its color, cleavage, and unusual luster. It commonly occurs in magic igneous rocks and was named from the Greek word meaning "opponent" because of its refractory nature.

Discovered in 1801 in Norway, this mineral’s name comes from the Latin word "anthophyllum," meaning "clove," in reference to its common clove-brown color. Amosite, an iron-rich variety of this mineral, occurs in long, flexible fibers and is used as asbestos.

Cordierite was named after Pierre Louis A. Cordier (1777-1861), a French mining engineer and geologist, who first studied the species. This mineral commonly alters to some form of mica. It is found as an accessory mineral in granite, gneiss, schists, and in contact metamorphic zones. The transparent variety has been used as a gem known by jewelers as saphir d'eau.

A very minor copper ore, chrysocolla’s name was first used by Theophrastus in 315 BC and comes from the Greek chrysos meaning "gold" and kola meaning "glue," in allusion to the name of the material used to solder gold. This mineral is typically found as glassy botryoidal, rounded masses, or bubbly crusts in green, bluish-green, and blue colors. It can be confused with turquoise but can be distinguished from it by seeing if it sticks to your tongue.

Named after the Dutch Colonel, H. Von Prehn (1733-1785), this mineral was discovered in 1788 in South Africa. It occurs as a secondary mineral lining cavities in basalt and is characterized by its green color and crystalline aggregates forming reniform surfaces.

Discovered in 1853 in Romania, this mineral was named in allusion to the hemimorphic (different at the ends) morphology of the crystals. An ore of zinc, this mineral occurs as a secondary mineral found in the oxidized portion of zinc deposits.

The vitreous luster of this gem mineral is what distinguishes it from quartz. In the 1940s, a 596-pound crystal was found in Minas Gerais, Brazil. The name is derived from Topazion, an island in the Red Sea.