Granite is an intrusive igneous rock comprised primarily of feldspar and quartz that has a long history of use as a building material. Some types of granite, however, such as unakite, are primarily utilized for more aesthetic purposes.

View a second and third image of Unakite

Unakite is a popular semiprecious gemstone often described as an epidotized granite. It usually appears as a mottled red or salmon pink and green stone. The green hue is attributed to the significant presence of epidote, a yellow-green silicate mineral that is sometimes produced during metamorphism of basic igneous rocks. The pink or red coloration, on the other hand, generally stems from pink orthoclase feldspar and quartz. The unique appearance of the highly polishable rock makes it an interesting choice for beads, jewelry, paperweights, and other ornamental items.

In nature, unakite typically occurs in granitic masses, especially in dikes and lenses. The type locality of the rock is the Unaka Range of the Smoky Mountains in eastern Tennessee, from which it derives its name. Unakite can also, however, be found in a number of other states, including North Carolina where it enjoys the designation of official state rock, as well as Africa. Relatively compact, the rock exhibits a hardness that ranks a 6 to 7 on the Mohs scale and a specific gravity of 2.86 to 3.2.

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