2.8" Bi-Colored Elbaite Tourmaline Cluster - Cruzeiro Murta, Brazil

Elbaite is a form of tourmaline and is perhaps the most multicolored mineral. It has been discovered in virtually every color of the spectrum and has dramatically increased in popularity since the 1990s. While specimens are commonly faceted into gemstones, most high quality crystals are left as is, or are cut and sold as cross-sectional slices. Elbaite forms as short, stubby, and/or elongated prismatic crystals, often with striations that run along their length. Aggregates of elbaite can occur as botryoidal, columnar, radiating crystals, and in compact masses.

Elbaite has a variety of names (classic and modern) depending on the colors it presents, including achroite (colorless variety), blue cap tourmaline, chrome tourmaline (green variety caused by chromium impurities), fluor-elbaite, indicolite (blue variety), Moor's head tourmaline, mushroom tourmaline, Paraiba tourmaline, rubellite (pink-red variety), siberite (purple variety), verdelite (green variety), and watermelon tourmaline (green exterior with red interior).

The chemical formula of elbaite is Na(Li,Al)3Al6(BO3)3Si6O18(OH)4