The Mineral elbaite
Elbaite is the most well-known and valuable form of Tourmaline. Most of the multicolored Tourmalines and almost all of the Tourmaline gemstones are of the Elbaite variety. Elbaite is
perhaps the most multicolored mineral, coming in virtually
every color of the spectrum. Multicolored crystals of Elbaite are well known and unsurpassed in beauty.
Elbaite has many interesting optical properties. Many green and blue
specimens are strongly pleochroic. When viewed through their
vertical axis, such specimens appear darker in color than when seen
through their horizontal axis. Certain Elbaites exhibit a cat's eye effect when
polished into cabochons.
Chemical Formula
Na(Li,Al)3Al6(BO3)3Si6O18(OH)4
Color
Elbaite is one of the most varied minerals in terms of color. Colors include green, red, pink and blue. White, colorless, black, brown, yellow, orange, and purple colors are less common. Crystals are frequently multicolored, containing two or more distinct colors. Some specimens are pleochroic.
Properties
Streak
White |
Hardness
7.0 - 7.5 |
Transparency
Transparent to translucent |
Specific Gravity
2.9 - 3.0 |
Luster
Vitreous |
Cleavage
3,2 |
Fracture
Conchoidal to uneven |
Tenacity
Brittle |
Crystal Habits
Usually as elongated prismatic crystals that are heavily
striated. Also as short, stubby, prismatic crystals. Most Elbaite crystals have a rounded, triangular cross-section. Seldom in
tabular crystals. Aggregates include columnar, radiating,
botryoidal, in dense groups of tiny, elongated
needles, and in compact masses. Crystals may be curved or warped, and in some cases may have their growth interrupted by host rock with the same crystal appearing in two parts of a matrix.
Varieties
The variety names below that are prefixed with a check are the classic variety names. Modern-day names and trade names are prefixed with an "x".
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Form of Elbaite Tourmaline with its top portion having a dark blue color, with the rest of the body having a red or pink color. Blue Cap Tourmaline is cherished by collectors.
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Form of Elbaite where part of the hydroxyl is replaced with
fluorine. Although Fluor-elbaite was known for quote some time, it was only recognized as a distinct mineral
species by the IMA in 2011, with the following chemical formula: Na(Li,Al)3Al6(BO3)3Si6O18(OH)3F
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Lightly tinted, transparent Elbaite Tourmaline with a black top that is well known from the island of Elba, Italy.
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Elbaite Tourmaline from Burma (Mynamar) with an odd-shaped fan-like protruding botryoidal growth off the top of a crystal that resembles the formation of a mushroom.
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Neon blue variety of Elbaite Tourmaline that originated in Paraiba, Brazil. Its interesting color is caused by inclusions of copper.
Uses
Elbaite is form of Tourmaline used as a gemstone. Its popularity has greatly increased
since the 1990's, and this has also been reflected in the astronomical
prices demanded from the finest Elbaite. Elbaite Tourmaline is cut into all forms and styles for jewelry use. All the colors of Elbaite, especially multicolored gems, are used in jewelry.
See the gemstone section on Tourmaline for more detailed information.
Elbaite form in extremely aesthetic slender crystals that are
highly valued by collectors. It is one of the most prized
minerals, and fine crystals can be among the most beautiful examples in
the mineral kingdom. Instead of being faceted, many Elbaite crystals are
preserved for their beauty. Thick, elongated crystals are sometimes
sliced into sections and sold as "Tourmaline cross sections".
Noteworthy Localities
Among the most noteworthy sources of Elbaite is the state of Minas Gerais, Brazil, where outstanding forms and colors of this beautiful Tourmaline are found in numerous pegmatite localities. Specific famed locality names in Minas Gerais include Aracuai, Barra do Salinas, Conselheiro Pena, Golconda, Governador Valadares, Itambacuri, Ouro Preto, Sao Jose do Safira, Taquaral, and Virgem de Lapa. An very popular yet rare neon blue Elbaite, affectionately called Paraiba Tourmaline, came from the Paraiba Mine in Sao José da Batalha, Paraiba, Brazil; and distinctly beautiful raspberry to ruby-red Elbaite var. Rubellite from the Jonas Mine, Itatiaia, Minas Gerais, Brazil. An outstanding producer of some of the highest quality collector crystals of Elbaite, with especially prominent terminations, is the Pederneira Mine in Sao Jose do Safira.
Afghanistan is also known for its outstanding Elbaite, especially at the mine fields of Paprok and Mawi in Nuristan, Kunar Province. Excellent Elbaite comes from the mountains of Northern Pakistan at Stak Nala, Skardu, Gilgit District. An odd, radiating botryoidal mushroom-shaped Elbaite ("Mushroom Tourmaline") comes from Mogok, Mynamar (Burma), often in a pink to deep red color. An important Russian locality, which is producing a dark red Elbaite, is the Malkhan Pegmatite, Transbaikalia, in Siberia.
The type locality for Elbaite, where this mineral was first described, is on the on the island of Elba, Italy, in the deposits of San Piero in Campo and nearby Sant'Ilario in Campo. These deposits have produced very old historic Elbaite, especially the classic Moor's Head Tourmalines with black caps.
African localities include the Mt. Ibity area in the Sahatany Pegmatite Field, in Antananarivo Province, Madagascar; Otjua and Usakos, Karibib District, Erongo, Namibia; Alto Ligonha, Zambezia Province, Mozambique; and the Jos Plateu, Nigeria.
In the U.S., Southern California produces some of the most outstanding Elbaite. The most important locality is Pala, San Diego Co., where the specific deposits are the Tourmaline King Mine, the Tourmaline Queen Mine, the Stewart Mine, the Pala Chief Mine, and the Elizabeth R. Mine. The Himalaya Mine, in nearby Mesa Grande, is also a world-famous Elbaite producer. Other important Southern California localities in San Diego Co. include the Little Three Mine, Ramona; and the Cryo-Genie Mine, Warner Springs.
On the East Coast of the U.S., in New England, are some of the classic and famous Tourmaline quarries. Most noteworthy is the state of Maine, which has several important deposits, the most famous being the Dunton Quarry, Newry; and Mt. Mica, Paris, both in Oxford Co.; and Mt. Apatite, in Auburn, Androscoggin Co. In Connecticut, fine green Elbaite once came from the Gillette Quarry, Haddam, Middlesex Co.
Distingushing Similar Minerals
Beryl - Striations are much finer and are horizontal, and usually more hexagonal in crystal form.
Apatite - Crystals lack striations , softer (5).
.aspx >Epidote - Softer, different crystal habits.
Schorl - Always opaque.