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Chemical Formula | Pb5(VO4)3Cl |
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Composition | Lead chloro-vanadate. The vanadate radical (VO4) may be partially replaced by an arsenate radical (PO4), thus forming a series with Mimetite. |
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Variable Formula | Pb5([V,As]O4)3Cl |
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Color | Bright red, orange, brown, yellow-brown, yellow. Crystals may also be multicolored. |
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Streak | Light yellow to nearly white |
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Hardness | 2½ - 3 |
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Crystal Forms and Aggregates |
(Hexagonal) Occurs as prismatic and stubby hexagonal crystals, which may be partially hollow. Crystals are occasionally pyramidal. Also occurs as small hexagonal plates, as pyramidal clusters, fibrous, crusty, radiating, acicular, and reniform. |
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Transparency | Transparent to translucent |
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Specific Gravity | 6.7 - 7.2 |
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Luster | Greasy to adamantine |
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Cleavage | None |
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Fracture | Conchoidal to uneven |
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Tenacity | Brittle |
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In Group | Phosphates ; Vanadates ; Apatite group |
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All About | Vanadinite is a member of the Apatite group, a group of isomorphous hexagonal minerals. It is very similar in structure
and appearance to Mimetite, and may be partially replaced by it. The intermediary member between Vanadinite and
Mimetite is known as "Endlichite". Specimens from some localities may darken and lose transparency upon prolonged exposure to light. |
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Uses | Vanadinite is an important ore of vanadium, and a minor ore of lead where it occurs with more abundant lead minerals. Its distinctive color makes it very popular among mineral collectors. |
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Striking Features | Color and luster, crystal habits, and occurrences |
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Popularity (1-4) | 2 |
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Prevalence (1-3) | 2 |
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Demand (1-3) | 1 |
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Distinguishing Similar Minerals |
Pyromorphite - Usually greener in color, and
occurs in hollow crystals. Otherwise cannot be
distinguished with practical methods Mimetite - Usually redder in color. Otherwise cannot be distinguished with practical methods Apatite - Harder (5) Red Beryl - Much harder (7½ - 8), different environment then Vanadinite |
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Commonly Occurs With |
Galena, Wulfenite, Barite, Calcite, Descloizite, Limonite |
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Noteworthy Localities |
The finest Vanadinite is from Mibladen,
Morocco, where it occurs as blood-red hexagonal plates
and "barrels". Beautiful crystals also come
from Touisset, Morocco; Tsumeb, Namibia; Broken Hill,
Zambia; and Cordoba, Argentina. The largest Vanadinite
crystals were found in Abenab, Namibia, but they were all
coated with a thick ugly coating of brown Descloizite. In Mexico, fine brown crystals are found in Villa Ahumada, Los Lamentos, Chihuahua, Mexico. The only significant occurrences of Vanadinite in the U.S. are in the arid southwest. Localities in Arizona include the Apache Mine, Globe district, Gila Co.; the Hamburg Mine, Yuma Co.; the Mammoth Mine, Tiger, Pinal Co.; and the Old Yuma Mine, Pima Co. Yellow "Endlichite" specimens are famous from the Lake Valley and Hillsboro district, Sierra Co., New Mexico. In California, Vanadinite is found in the El Dorado Mine, Indio, Riverside Co., California. |
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Picture Icon Links |
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Picture Links | Sorry. No Images currently available. |
