Vanadinite

Vanadium is found in about 65 different minerals among which are carnotite, roscoelite, vanadinite, and patronite, important sources of the metal. Vanadium is also found in phosphate rock and certain iron ores, and is present in some crude oils in the form of organic complexes. It is also found in small percentages in meteorites. 

Vanadin-blelerz, n., -bleispat, m. vanadinite. -chlond, n. = Vanadiumchlorid. -eisen, n. ferro vanadium. 

Minerals can form colorful regular crystals. Shown here are vanadinite, Pbj (V04)3 Cl lefty, quartz, Si02 center)-, fluorapatite, Caj (P04)3 F top right)-, and stibnite,... 

Occurrence. Important minerals are carnotite K(U02)V04 3/2 H20, more important as a uranium ore, vanadinite Pb5(V04)3Cl and some complex sulphides. It occurs also in certain crude oils and may be recovered from dusts after combustion. 

Vanadium is not found in its pure state. Small amounts of vanadium can be found in phosphate rocks and some iron ores. Most of it is recovered from two minerals vanadinite, which is a compound of lead and chlorine plus some vanadium oxide, and carnotite, a mineral containing uranium, potassium, and an oxide of vanadium. Because of its four oxidation states and its ability to act as both a metal and a nonmetal, vanadium is known to chemically combine with over 55 different elements. 

Vanadiums principal ores are roscoelite, patronite, vanadinite, and carnotite, which are found in the states of Idaho, Montana, Arkansas, and Arizona as well as in Mexico and Peru. It is also a by-product from the production of phosphate ores. 

Natural fibrous materials are identified somewhat by chance. For example, there are seven vanadate and seven vanadium oxysalt minerals on the list of fibrous minerals. These species are composed of a rare element, vanadium, but the fibrous samples may have attracted attention because they are often brightly colored. Vanadinite [Pb5(V04)3Cl] for example, is bright orange-red. Further, the list of natural mineral fibers we have compiled contains seventy-seven phosphate species. So many phosphates are listed because detailed descriptions of these mostly quite rare minerals were readily available (Nriagu and Moore, 1984). 

In Great Britain vanadium has been found associated with the lead ores at Wanlockhead, in the Lead Hills, Dumfriesshire, as vanadinite,a and associated with the copper deposits at Alderley Edge and at Mottram St. Andrews, Cheshire, as mottramite. The latter was at one time mined and treated for its vanadium, but commercially profitable supplies of this ore have now given out. Vanadium has also been reported to occur in titaniferous iron ores at Antrim,3 and in rocks at Wicklow and Giant s Causeway.4... 

Commercial sources of vanadium which are now disused arc the roscoelite deposits in Colorado, the vanadinite deposits near Santa Marta in Spain, and the mottramite deposits in Cheshire and Shrewsbury.1 It is of some interest to note that efforts are being made to extract the vanadium from the Taberg iron ores or slags, in which vanadium was originally discovered,2 and from the Rhodesian deposits.3... 

This lead salt is the artificial form of the important natural ore vanadinite.)... 

VANADINITE. The mineral vanadimte corresponds to the formula Pb VO Cl, being composed of lead chloride and lead vanadate in the proportion of 90.2% of the former and 9.8% of the latter. It crystallizes in the hexagonal system, is usually prismatic, but the ciystals are often skeletal or cavernous it may be found in crusts. Its fracture is uneven brittle hardness. 2.75-3 specific gravity. 6.86 fresh fractures show a resinous luster color, yellow, yellowish-brown, reddish-brown, and red streak, white to yellowish translucent to opaque. Vanadinite, not a common mineral, occurs as an alteration product in lead deposits. It is found in the Ural Mountains, Austria, Spain, Scotland, Morocco, the Transvaal, Argentina, and Mexico, In the United States it occurs in Arizona, New Mexico, and South Dakota, It is used as an ore of vanadium and to some extent of lead as well. It is interesting to note that this mineral was first described as a chromate upon its discovery in Mexico in 1801, It was not until the discovery of the element vanadium in 1830 that the true nature of this compound was known. 

In reinen Phosphatapatiten vermag Blei nur in kleinen Anteilen fur Calcium einzutreten, wahrend z.B. Vanadinit Pb5[Cl[(V04)3] nur geringe Calciumgehalte aufweist. 

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