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Wulfenite is determined in the well known thallium deposite Allchar, Macedonia. This is the first discovery of lead mineral in the deposit. Measured Pb isotopic ratios: 206Pb/204Pb = 18.327 - 18.378, 207Pb/204Pb = 15.675 - 16.634, 208Pb/204Pb = 38.494 - 38.584, show a common lead type. The lead present in the wulfenite is due to a previous decay of U and Th and not as a result of transformation 205Tl to 205Pb caused by interaction of neutrino with Tl.

Molybdenum is an important trace element in biology and is found in a multitude of redox active enzymes as well as in the N2 reducing nitrogenases. In nature molybdenum occurs mainly as molybdenite, MoS2, wulfenite, PbMoO4 and as soluble salts of MoO42- in the sea. The adaptation of Mo by bacteria, plants and animals as a metal of choice at first appears paradoxical given the perceived rarity of the element. The paradox is not there however if one realizes that in fact Mo is one of the more abundant elements on the planet and constitutes the most abundant redox active transition element in the oceans1.

High-pressure Raman scattering measurements have been performed in wulfenite (PbMoO4) for both bulk and nanocrystalline powders up to 22 GPa. Our Raman scattering measurements evidence the phase transition from the tetragonal scheelite structure to the monoclinic M-fergusonite structure in both bulk and nanocrystalline powders above 10.8 and 13.4 GPa, respectively. The pressure dependences of the Raman active modes in both structures were compared and discussed based on our theoretical results obtained from lattice dynamics ab initio calculations. © 2012 American Institute of Physics., Financial support from the Spanish ConsoliderIngenio 2010 Program (Project No. CDS2007-00045) is acknowledged. The work was also supported by Spanish MICINN under Projects MAT2010-21270-C04-01/03/04 and from Vicerrectorado de Investigacion de la Universitat Politecnica de Valencia under Projects UPV2011-0914PAID-05-11 and UPV2011-0914 PAID-05-11. Supercomputer time has been provided by the Red Espanola de Supercomputacion (RES) and the MALTA cluster.

Queitite, [Pb4Zn2(SO4)(SiO4)(Si2O7)], is an extremely rare mineral. This is the first recorded Scottish occurrence and only the third world-wide. Queitite was first described by [Keller et al. (1979)][1] from Tsumeb, Namibia where it occurs as euhedral bladed crystals on a matrix of lead-copper ore associated with willemite, quartz, melanotekite, alamosite, larsenite, leadhillite, mimetite and wulfenite. There has been only one find of a few specimens although in the past the mineral may have been mistaken for pale yellow adamite. In 1987 queitite was identified on a small specimen from the dumps of the Old Dutch (or No. 2) level of the Red Gill Mine, Caldbeck Fells, Cumbria ([Braithwaite et al. 1989][2]). This specimen consists predominantly of massive cerussite with subordinate quartz. A cavity contains leadhillite, susannite and caledonite in addition to the queitite, all deposited after the cerussite. This queitite forms a white, drusy and minutely botryoidal encrustation (with silky, fibrous structure) about 0.5 mm thick. A small specimen (approximately 13 mm3), collected by Mr Neil Hubbard of Leicester, from the old mine dumps on Horner’s Vein, Leadhills, Lanarkshire, was handed into the Royal Museum of Scotland for identification. The specimen comprises quartz and corroded galena with secondary lead minerals typical of the area; in this case cerussite, susannite, mettheddleite and pyromorphite. A 4 mm-long cavity contains medium to dark greyish brown hemispheres up to 1 mm across. These are aggregated together so that the cluster fills the length of the cavity. Where broken the hemispheres show a fibrous colour-zoned, . . . [1]: #ref-2 [2]: #ref-1

A study of the morphology of chalcopyrite, stannite, wulfenite and manganite shows that the existence of a structural pseudo-symmetry has an influence on the relative importance of the different forms in these crystals. In particular, the reticular planes possessing, in relation to the pseudo-symmetry, a spacing which is a submultiple of the true spacing correspond to forms whose development is in general less common than that predicted by the law of Donnay & Harker.

An attempt is made here to describe occurrences and paragenetic sequences of the supergene Zn and Pb minerals in 3 districts representing varying mean temperatures and humidities. The facts observed in field and laboratory are interpreted in the light of physical chemistry, assuming equilibrium conditions. The stability relationships between smithsonite, hydrozincite, and zinc hydroxide are defined in terms of pH and total carbon dioxide concentrations in the aqueous solution system, or of the partial pressure of carbon dioxide in the dry system. The stability fields of hemimorphite and willemite are also discussed. The study explains the common occurrence of hydrozincite in arid regions, and the scarcity of this mineral in humid regions. The common occurrences of smithsonite and hemimorphite in the southern Appalachian district, and the predominance of smithsonite over hydrozincite and hemimorphite in the Upper Mississippi Valley district can be explained by the pH of the ground waters and soils. The stability fields of supergene lead oxide minerals, wulfenite, cerussite, anglesite, and Cd minerals are calculated in terms of pH, Eh, and total S concentration or total carbon dioxide concentration in solution. The paragenesis of the Pb minerals and the mobilization of molybdate and Cd ions are discussed. The results of the spectrochemical analyses indicate that Mo and As in the supergene facies were derived from galena, whereas V and P were derived from the limestones and shales.

The Glove Mine is located on the southern extremity of an isolated syncllnal sedimentary block of Paleozoic and Cretaceous sediments on the southern flank of the Santa Rita Mountains in Santa Cruz County about forty miles south of Tucson, Arizona. Fluids probably associated with a Laramide (?) quartz monzonite in- trusivehave deposited argentiferous galena, sphalerite, chalcopyrite, pyrite, and quartz along permeable zones caused by fault intersections within a favorable limestone bed of the Pennsylvanian-Permian Naco group. As a result of extensive oxidation, only relics of the primary sulfides exist in the mined portion of the deposit. Cerussite, and lesser amounts of angle- site, wulfenite, smithsonite, and other oxidation products of the primary sulfides have been conten{rated in solution caverns. The ore body can be divided into three general zones on the basis of metal content and mineral assemblage. These zones are (A) the upper oxidized and leached zone, (B) the silver-enriched intermediate zone, and .(C) the sulfide zone. The behavior of individual metals and minerals is dependent upon local Eh-pH conditions as well as other environmental factors affecting mineral stability. In response to changes in environment, mineral and metal assemblages vary not only between the zones but within them as well.

The isotopic abundance of molybdenum has been analyzed in molybdenite and wulfenite minerals from six locations all over the world and no anomalies have been found greater than 0.15%. No results were obtained with respect to differences in mass-dependent fractionation of the samples because of overriding instrumental mass discrimination.

The Struy lead mines (Six-inch ordnance Survey, Inverness-shire, sheet 17) are situated on the west side of Strath Glass, about two miles south-west of Struy village, and comprise three distinct sets of small long-abandoned workings, two of them being in the nature of trials only. All three workings are shown on the six-inch map, and are on veins traversing the Moine schists. The Geological Survey Memoir of the district says that four veins may be traced on the hill face between the Dùn south of Struy school and Crelevan; if this is correct there are two outcrops I have not seen. The mines are on what was until a few years ago part of Lord Lovat's estate. The date of their discovery is not known, but they were apparently worked about the year 1818 by Thomas Alexander Fraser (afterwards 12th Lord Lovat) at the same time as his graphite mine in Strath Farrar; most of the work seems, however, to have been done by him between 1838 and 1845, when miners were brought from England and housed in cottages specially built for them in Struy village. In 1864 the Loch na Mèine workings were cleared and prospected, but since then no further work has been done.

A new approach for seeking PBC's applicable to every known structure has been applied to the wulfenite structure. The following PBC's have been analyzed: straight - [110], [021] and [001], and zigzag chains - [100], [111], [131], [331], [011], and their symmetrical equivalents. It is established through a comparison with the zone development of the crystals with scheelite type structure that all chains determined and no others, effect the morphology. The chains are also distinguished according to the distances between the neighbouring metal Pb and Mo bound with oxygen. Chains within which this distance is shortest, i.e. 3.84 A only determine a single F-form {001}, the F-forms {011}, {112}, {013} and {010} are added for chains which have a distance of 4.10 A. If all chains derived are taken into account, {121} and {110} become F-forms, too. The morphological variations of the crystals with scheelite type structure are also analyzed using the PBC method.

The Satsuma-Iwojima volcano has been emitting continuously high temperature (600° to 900°C) gases for at least 800 years. We identified the minerals that form in response to closed-system cooling of these gases and from air-mixing reactions. Major differences compared with the sublimates observed at other volcanoes are the occurrence of wulfenite (PbMoO4) and several mixed chlorides. This is the first report of wulfenite in fumarolic deposits. Thermochemical modeling shows that wulfenite precipitates between 540° and 490°C from a gas with lower sulfur content and/or higher fO2, and a higher Mo content (log fSO2 = −2.1, log fH2S = −5, log ffO2 = −18.6, log fH2MoO4 = −4.5, T = 500°C) than the previously reported gas composition. The occurrence of abundant K, Pb, Fe, Zn, Rb and Cs mixed chlorides may be promoted by the low S/Cl of the Satsuma-Iwojima high temperature gases. Natural sublimates of metallic elements (molybdenite, wulfenite, anglesite, Tl-Pb and Tl-Bi sulfides, Mo oxydes and Pb oxides) are deposited along the fumarolic conduit and on the ground under conditions of variable temperatures and fO2. The increase in fO2 due to the mixing of the gases with the atmosphere reduces the volatility of several elements (As, Sn, Na, K and Pb) by promoting their condensation at higher temperatures. As air mixes with volcanic gas in the fumarolic plume, we can expect to find these metals as aerosols.

In October 1875 the late J. G. Goodchild recorded his then recent discovery of a mineral which he stated 'he believed' to be wulfenite and which he had found on an old mine dump near Carrock Fell, Troutbeck, Cumberland. One specimen only was, I believe, found by Mr. Goodehild, and this he presented to the Carlisle Museum, where it has been seen by myself, the label bearing the more precise locality of Brandy Gill.

The yellow and red coloration of wulfenites is caused by small traces of chromium. This is shown by spectrographical and colorimetrical analyses. It is supposed that this element is present as chromate. Syntheses of wulfenite by means of adding chromium as chromate supports this view. In red vanadinites of Arizona chromium is found too. The contents of vanadium are also determined. A wulfenite of Arizona contains neodym and praseodym amounting in sum to about 0.1%. The irradiation of filtered ultraviolet light generally shows no fluorescence in wulfenites at normal temperatures, but in the coldness of liquid air a bright yellow-green fluorescence is visible. If the wulfenites are heated to glowing, they fluorescence at normal temperatures. A connection seems to exist with the content of chromium.

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SummaryThe piezoelectrically active dust, wulfenite, of maximum particle size .074 mm was administered intratracheally to 38 mice. In no instance was there evidence of cellular reaction to the wulfenite in the lungs of these animals. The theory that a substance, by virtue of its possession of piezoelectric properties, can produce reaction in the living organism requires further confirmation.

The role of crystal defects and related microstructures in controlling the mechanical properties and other behavior of metals and alloys is well known, and materials characterization, particularly microstructural, has become an integral part of metallurgical and materials engineering. Similar characterization would also seem to be valuable in other more general areas of mineral processing and mineral engineering, particularly since it might be expected that crushing, grinding, leaching, and other forms of extraction of mineral and metal values would also be dependent upon the existing microstructure, or the development of microstructure with processing. While there has been a considerable effort made in recent years to characterize mineral microstructures in general1, there have been few attempts to characterize the microstructures of ore minerals.