Ore mineralogy of the Waschgang gold-copper deposit,upper carinthia,Austria     

Dr. W. H. Paar  Dr. T. T. Chen 《Mineralogy and Petrology》1982,30(3):157-175

Summary The gold-copper deposit at Waschgang (Southern Goldberg mountains, Upper Carinthia) belongs to a type of stratiform, dominantly pyritic deposit, which is hosted by greenschists (Alpine Kieslager;Friedrich, 1936). The ores occur as impregnations (ore type 1) and as massive ores (ore type 2) in prasinitic rocks of the Obere Schieferhülle of the Penninic unit. A N–S trending fault zone cuts the ore deposit to the W (Lettenkluft); the position of the displaced part is unknown.The mineralogical composition of type 1 ores is rather monotonous. Pyrite is the most important ore, minor components are chalcopyrite, bornite, sphalerite and magnetite. No visible native gold has been observed in this type of ore. Type 2 ores are dominated by chalcopyrite and are characterized by large amounts of visible native gold. The majority of these ores occur in the vicinity of the Lettenkluft.Type 2 ores carry a great variety of cogenetic mineral inclusions, of which several have been studied with the electron microprobe and investigated by X-ray methods. These include: tetradymite, Bi₂Te_1.81Se_0.13S; hessite, Ag₂Te; matildite, AgBiS₂; gladite, Cu_1.09Pb_1.14Bi_5.28S₉; krupkaite, CuPbBiS₆; pekoite, Cu_1.09Pb_0.97Bi_12.56S₁₈; (?) benjaminite, (Ag_2.72Cu_0.42)_3.14 (Bi_6.88Pb_0.12)₇(S_11.08Se_0.92)₁₂; pavonite, (Ag_0.74Cu_0.45)_1.19(Bi_2.86Pb_0.27)_3.13 (S_4.96Se_0.04)₅; (?) cupropavonite, (Cu_0.73Ag_0.4)_1.13(Bi_2.59Pb_0.83)_3.42S₅; and siegenite, (Ni_1.07Co_1.76Cu_0.19)_3.02S₄. Other components have been determined by qualitative and quantitative microscopy and include: bornite, idaite, mawsonite, sphalerite, millerite, magnetite, hematite, ilmenite, rutile and a variety of silicates.While the layered ore impregnations (type 1 ores) can be considered as being syngenetic with the associated volcanics of Jurassic age, a syn- to postkinematic (Alpidic) crystallization can be postulated for the type 2 ores. These ores are considered as remobilized and reconcentrated parts of the type 1 ores formed in tectonic stress zones. The crystallization of chalcopyrite and included ore minerals occurred during the cooling history of Alpidic metamorphism, for which in this region a maximum temperature of 500°C and pressures between 4–6 kb have been deduced from the mineral assemblage of the surrounding prasinites, consisting of albite with rims of oligoclase, epidote, chlorite, sphene and amphibole (Höck, 1980). Based onSpringer's limit of 300°C as approximately representing the maximum temperature at which natural members of the bismuthinite-aikinite mineral series have been formed, krupkaite and gladite with the intergrown pavonite type phases might have been deposited directly from solutions at or below 300°C. Unmixing of pekoite from gladite probably occurred at or below the same temperature.

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Zur Erzmineralogie der Gold-Kupfer-Lagerstätte Waschgang, Oberkärnten, Österreich

Zusammenfassung Die Gold-Kupfer-Lagerstätte Waschgang (südliche Goldberggruppe, Oberkärnten) ist dem Typus der stratiformen Kiesvererzungen in Grüngesteinen (Alpine Kieslager;Friedrich, 1936) zuzurechnen. Die Erzmineralisationen treten als stoffkonkordante Imprägnationen (Vererzungstypus 1) und als Derberze (Vererzungstypus 2) in Prasiniten der Oberen Schieferhülle des Penninikums auf. Das Erzlager wird im W an einer N–S streichenden Störung abgeschnitten; die Position des verworfenen W-Flügels ist nicht bekannt.Die Imprägnationserze sind in ihrer mineralogischen Zusammensetzung monoton; Pyrit als Haupterz überwiegt bei weitem die sporadischen Begleiter Kupferkies, Bornit, Sphalerit und Magnetit. Dieser Typus führt kein Freigold.Die von Kupferkies dominierten und an Freigold reichen Derberze treten vor allem im Bereich der Lettenkluft auf. Sie sind durch eine Vielfalt zum Teil komplex zusammengesetzter Einschlußminerale gekennzeichnet, von denen einige mittels Mikrosonde und röntgenographischer Methoden untersucht wurden: Tetradymit, Bi₂Te_1,81Se_0,13S; Hessit, Ag₂Te; Matildit, AgBiS₂; Gladit, Cu_1,09Pb_1,14Bi_5,28S₉; Krupkait, CuPbBiS₆; Pekoit, Cu_1,09Pb_0,97Bi_12,56S₁₈; (?) Benjaminit (Ag_2,72Cu_0,42)_3,14(Bi_6,88Pb_0,12)₇(S_11,08Se_0,92)₁₂; Pavonit, (Ag_0,74Cu_0,45)_1,19(Bi_2,86Pb_0,27)_3,13 (S_4,96Se_0,04)₅; (?) Cupropavonit, (Cu_0,73Ag_0,4)_1,13(Bi_2,59Pb_0,83)_3,42S₅; Siegenit, (Ni_1,07Co_1,76 Cu_0,19)_3,02S₄. Andere Mineralphasen wurden mittels qualitativer und quantitativer Mikroskopie bestimmt: Bornit, Idait, Mawsonit, Sphalerit, Millerit, Magnetit, Hämatit, Ilmenit, Rutil und Silikate.Während die stoffkonkordaten Imprägnationserze syngenetisch mit den assoziierten jurassischen Vulkaniten anzusehen sind, wird für die Derberze eine syn- bis postkinematische Kristallisation angenommen. Sie sind als remobilisierte und rekonzentrierte Teile der Imprägnationserze in tektonisch besonders beanspruchten Lagerstättenteilen anzusehen. Die Kristallisation des Kupferkieses und seiner Einschlußminerale erfolgte während der Abkühlungsphase der alpidischen Metamorphose, für die im betrachteten Gebiet eine Maximaltemperatur von ca. 500°C und Drucke zwischen 4–6 kb aufgrund der Petrologie der erzführenden Prasinite angenommen werden können. Die dafür maßgebende Paragenese besteht aus Albit mit Oligoklasrändern, Epidot, Chlorit, Sphen und Amphibol (Höck, 1980). Zieht man die vonSpringer (1971) ermittelte Stabilitätsgrenze von ±300°C für natürliche Mischkristalle der Bismuthinit-Aikinit-Reihe in Betracht, können für Krupkait und Gladit und den damit verwachsenen Pavonit-Phasen Bildungstemperaturen um oder unterhalb 300°C angenommen werden. Die Kristallisation dieser Minerale dürfte dabei direkt aus Lösungen erfolgt sein. Die als Entmischungsstrukturen interpretierten Gladit-Pekoit-Verwachsungen legen den Schluß einer primären Bildung beider Minerale als feste Lösung nahe, deren Zerfall vermutlich unterhalb von 300°C erfolgte.

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With 13 Figures

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Herrn em. Univ.-Prof. Dr.-Ing. O. M. Friedrich zum 80. Geburtstag in Dankbarkeit gewidmet

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This investigation forms part 2 of a major study on Genetic Types of Gold Deposits of the Alps.  相似文献   

Mineralogy and mineral chemistry of Bi-minerals: Constraints on ore genesis of the Beiya giant porphyry-skarn gold deposit,southwestern China     

《Ore Geology Reviews》2016

The Beiya deposit, located in the Sanjiang Tethyan tectonic domain (SW China), is the third largest Au deposit in China (323 t Au @ 2.47 g/t). As a porphyry-skarn deposit, Beiya is related to Cenozoic (Himalayan) alkaline porphyries. Abundant Bi-minerals have been recognized from both the porphyry- and skarn- ores, comprising bismuthinite, Bi–Cu sulfosalts (emplectite, wittichenite), Bi–Pb sulfosalts (galenobismutite, cosalite), Bi–Ag sulfosalt (matildite), Bi–Cu–Pb sulfosalts (bismuthinite derivatives), Bi–Pb–Ag sulfosalts (lillianite homologs, galena-matildite series), and Bi chalcogenides (tsumoite, the unnamed Bi₂Te, the unnamed Ag₄Bi₃Te₃, tetradymite, and the unnamed (Bi, Pb)₃(Te, S)₄). Native bismuth and maldonite are also found in the skarn ores. The arsenopyrite geothermometer reveals that the porphyry Au mineralization took place at temperatures in the range of 350–450 °C and at log fS₂ in the range of − 8.0 to − 5.5, respectively. In contrast, the Beiya Bi-mineral assemblages indicate that the skarn ore-forming fluids had minimum temperatures of 230–175 °C (prevailing temperatures exceeding 271 °C) and fluctuating fS₂–fTe₂ conditions. We also model a prolonged skarn Au mineralization history at Beiya, including at least two episodes of Bi melts scavenging Au. We thus suggest that this process was among the most effective Au-enrichment mechanisms at Beiya.  相似文献   

Phase relations in the systems Cu2S-PbS-Bi2S3 and Ag2S-PbS-Bi2S3 and their mineral assemblages     

Wu Daqing 《中国地球化学学报》1987,6(3):225-233

The phase diagrams of the systems Cu₂S-PbS-Bi₂S₃ and Ag₂S-PbS-Bi₂S₃ have been investigated in the present study. The paper is concerned with the complete solid solution between bismuthtite and aikinite above 300°C in the system Cu₂S-PbS-Bi₂S₃. The synthetic phases CuBi₃S₅ and Cu₃Bi₅S₉ have their solid solution ranges in the ternary system with 9 and 26 mole% PbS at maximum, respectively. A complete solid solution between PbS and AgBiS₂ divides the phase diagram of the system Ag₂S-PbS-Bi₂S₃ into two parts: Bi-rich and Ag-rich. All sulfosalt minerals and solid solutions, including pavonite ss, lillianite ss, heyovskyite and benjaminite are on the Bi-rich side. And divarant relations were found between pavonite ss -lillianite ss, benjaminite and bismuthtite as well as between lillianite ss -bismuthtite and galenobismutite. Synthetic experiments using LiCl-KCl flux technique show that when a minor amount of copper (less lwt.%) is added in, many of Ag-and Pb-bismuth sulfosalt minerals, for example, vikingite (Ag₅Pb₈Bi₁₃S₃₀), are synthesized successively, particularly at 400°C. So is heyrovskyite, which has a solid solution range with 3.7 mole% Cu₂S at maximum in the system Cu₂S-PbS-Bi₂S₃.  相似文献   

Pb−Bi−(Cu)-sulfosalts in Paleozoic gneisses and schists from Oberpinzgau,Salzgurg province,Austria     

Dipl.-Ing.Dr. W. H. Paar  Dr. T. T. Chen  Prof. Dr. H. Meixner 《Mineralogy and Petrology》1980,27(1):1-16

Summary Pb–Bi–(Cu)-sulfosalts occur as minor minerals widely distributed in rocks of the Penninic unit (gneisses, schists, metavolcanics, etc.), Oberpinzgau, Salzburg. The sulfosalts have been investigated by ore microscopy, X-ray diffraction and electron microprobe analysis. The phases identified are: heyrovskyite, cosalite (Moaralm, Sedl, and Wiesbachrinne in the Habach Valley), lillianite (Moaralm, Sedl; Modereck near the Fuscher Valley), galenobismutite (Bärenbad in the Hollersbach Valley) and Bi-bearing galena. Heyrovskyite (Moaralm) has a composition close to Pb₆Bi₂S₉, with Ag contents between 0.2 (Sedl) and 0.6 (Moaralm) wt.%. Lillianite has the composition Pb_2.86–2.91 Bi_2.08–2.17Ag_0.04–0.08 S₆, and cosalite, Pb_1.81–2.04 Bi_1.92–2.02 Ag_0.02–0.06 Cu_0.11–0.18S₅. The average chemical composition of galenobismutite is Pb_1.25Bi_1.6Sb_0.1Cu_0.1Ag_0.02Fe_0.1S₄. Needle-like inclusions of a joseite-type mineral, joseite-A (Bi,Pb)_4.01 Te_0.9S_2.08, and irregular to needle-like grains of native bismuth usually occur along the elongation direction of the lath-like galenobismutite crystals.The occurrences can be divided into two types: 1) stratiform Pb–Bi sulfosalts which occur only in the quartzite intercalations of the Paleozoic Habach unit (Frasl, 1958), and 2) alpidic vein type Pb–Bi sulfosalts which occur in quartz veins intersecting gneisses and are considered to be the remobilization products of the first type. Temperature of formation for heyrovskyite in this region is estimated at between 400±25°C and 500°C. Most probably, the assemblage heyrovskyite-lillianite-galena (Moaralm) was formed at or below 473°C.

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Pb–Bi–(Cu)-Sulfosalze in paläozoischen Gesteinen des Oberpinzgau, Salzburg, Österreich

Zusammenfassung Pb–Bi-Sulfosalze verschiedener Vorkommen des Oberpinzgau, Salzburg, wurden mittels Erzmikroskopie, röntgenographischer Methoden und Mikrosonde untersucht. Folgende Phasen wurden identifiziert: Heyrovskyit, Cosalit (Moaralm, Sedl und Wiesbachrinne; alle Habachtal), Lillianit (Moaralm, Sedl; Modereck nahe des Fuschertales), Galenobismutit (Bärenbad, Hollersbachtal) und Bi-hältiger Bleiglanz. Heyrovskyit (Moaralm) ist nahezu Pb₆Bi₂S₉, mit Ag-Gehalten zwischen 0,2 (Sedl) und 0.6 (Moaralm) Gew.%, Lillianit Pb_2,86–2,91Bi_2,08–2,17Ag_0,04–0,08S₆, und Cosalit Pb_1,81–2,04Bi_1,92–2,02Ag_0,02–0,06 Cu_0,11–0,18S₅. Galenobismutit ist Pb_1,25Bi_1,6Sb_0,1Cu_0,1Ag_0,02Fe_0,1S₄. Nadelige Einschlüsse von Joseit-A, (Bi, Pb)_4,01Te_0,9S_2,08, und unregelmäßige bis nadelige Körner von ged. Wismut treten entlang der Längsrichtung der Galenobismutit-Kristalle auf. Die Mineralisationen sind an stratiforme, sulfidreiche Quarzlagen (Typus 1, z. B. Bärenbad) oder an diskordante Quarzgänge (Typus 2; alle anderen Vorkommen) gebunden. Typus 1 tritt innerhalb der altpaläzozischen Habachserie (Frasl, 1958), Typus 2 in Randbereichen dieser zu den Gneismassen der Habachzunge (z. T. auch in letzteren) auf. Die dem Typus 2 zugerechneten Vererzungen werden als Remobilisationsprodukte der altpaläozoischen Mineralisationen (Typus 1) angesehen.Die Bildungstemperatur des Heyrovskyit dürfte im betrachteten Bereich zwischen 400±25°C und 500°C gelegen haben; eine Bildungstemperatur von 473°C oder wening darunter wird für die Assoziation Heyrovskyit-Lillianit-Bleiglanz in Anlehnung an experimentelle Untersuchungen vonSalanci undMoh (1969) angenommen.

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With 4 Figures

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This investigation forms part of a wider study Genetic types of gold deposits in the Alps.  相似文献   

Phase relations and mineral assemblages in the Ag-Bi-Pb-S system   总被引：1，自引：0，他引：1  

James R. Craig 《Mineralium Deposita》1967,1(4):278-306

Phase relations within the Ag-Bi-S, Bi-Pb-S, and Ag-Pb-S systems have been determined in evacuated silica tube experiments. Integration of experimental data from these systems has permitted examination and extrapolation of phase relations within the Ag-Bi-Pb-S quaternary system. — In the Ag-Bi-S system liquid immiscibility fields exist in the metal-rich portion above 597±3°C and in the sulfur-rich portion above 563±3°C. Ternary phases present correspond to matildite (AgBiS₂) and pavonite (AgBi₃S₅). Throughout the temperature range 802±2°C to 343±2°C the assemblage argentite (Ag₂S) + bismuth-rich liquid is stable; below 343°C this assemblage is replaced by the assemblage silver + matildite. — Five ternary phases are stable on the PbS-Bi₂S₃ join above 400°C — phase II (18 mol-% Bi₂S₃), phase III (27 mol-% Bi₂S₃), cosalite (33.3 mol-% Bi₂S₃), phase IV (51 mol-% Bi₂S₃), and phase V (65 mol-% Bi₂S₃). Phase IV corresponds to the mineral galenobismutite and is stable below 750±3°C. Phases II, III, and V do not occur as minerals, but typical lamellar and myrmekitic textures commonly observed among the Pb-Bi sulfosalts and galena evidence their previous existence in ores. Phase II and III are stable from 829±6°C and 816±6°C, respectively, to below 200°C; Phase V, stable only between 730±5°C and 680±5°C in the pure Bi-Pb-S system is stabilized to 625±5°C by the presence of 2% Ag₂S. Experiments conducted with natural cosalites suggest that this phase is stable only below 425±25°C in the presence of vapor. — In the Ag-Pb-S system the silver-galena assemblage is stable below 784±2°C, whereas the argentite + galena mineral pair is stable below 605±5°C. — Solid solution between matildite and galena is complete above 215±15°C; below this temperature characteristic Widmanstätten structure-like textures are formed through exsolution. Schematic phase relations within the quaternary system are presented at 1050°C, at 400°C, and at low temperature.

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Zusammenfassung Die Phasenbeziehungen in den Systemen Ag-Bi-S, Bi-Pb-S und Ag-Pb-S wurden durch Versuche in evakuierten Quarzglasröhrchen bestimmt. Die Auswertung aller experimentellen Daten gestattete eine Extrapolation der Phasenbeziehungen im quaternären System Ag-Bi-Pb-S. — Im System Ag-Bi-S besteht ein Zwei-Schemlzenfeld im metallreichen Teil über 597±3°C und im schwefelreichen Teil über 563±3°C. Die ternären Phasen entsprechen den Mineralien Schapbachit (AgBiS₂) und Pavonit (AgBi₃S₅). Zwischen 802±2°C und 343±2°C ist die Paragenese Silberglanz (Ag₂S) + Bi-reiche Schmelze stabil; unterhalb 343°C wird sie jedoch ersetzt durch die Paragenese Silber + Schapbachit. — Fünf ternäre Phasen sind stabil im Schnitt PbS-Bi₂S₃ oberhalb von 400°C: Phase II (18 Mol-% Bi₂S₃), Phase III (27 Mol-% Bi₂S₃), Cosalite (33.3 Mol-% Bi₂S₃), Phase IV (51 Mol-% Bi₂S₃) und Phase V (65 Mol-% Bi₂S₃). Phase IV entspricht dem Mineral Galenobismutit und ist stabil unterhalb 750±3°C. Die Phasen II, III und V kommen zwar nicht in der Natur vor, jedoch weisen typische myrmekitische und lamellare Gefüge, die man häufig in Pb-Bi-Sulfosalzen und deren Verwachsungen mit Bleiglanz beobachtet, auf die ehemalige Existenz solcher Phasen in diesen Erzen hin. Die Phasen II und III sind stabil von 829±6°C bzw. 816±6°C bis unter 200°C. Die Phase V, die im reinen System Bi-Pb-S zwischen 730±5°C und 680±5°C auftritt, wird in Gegenwart von 2% Ag₂S stabilisiert bis herab zu 625±5°C. Versuche mit natürlichen Cosaliten lassen darauf schließen, daß diese Phase nur unterhalb 425±25°C in Gegenwart einer Gasphase stabil ist. — Im System Ag-Pb-S ist die Paragenese Silber-Bleiglanz unterhalb von 784±2°C stabil, die Paragenese Silberglanz-Bleiglanz dagegen unterhalb 605±5°C. — Die Mischkristallreihe von Schapbachit und Bleiglanz ist vollständig oberhalb 215±15°C; unterhalb dieser Temperatur entstehen charakteristische Entmischungsgefüge ähnlich den Widmannstättenschen Figuren. Für das quaternäre System werden schematische Phasenbeziehungen für 1050°C, 400°C und eine noch tiefere Temperatur gegeben.

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Chemistry of some Pb-(Cu,Fe)-(Sb,Bi sulfosalts from France and Portugal. Implications for the crystal chemistry of lead sulfosalts in the Cu-poor part of the Pb2S2-Cu2S-Sb2S3-Bi2-Bi2S3 system     

Y. Moëlo  G. Roger  D. Maurel-Palacin  E. Marcoux  A. Laroussi 《Mineralogy and Petrology》1995,53(4):229-250

Electron microprobe analysis of Pb-Cu(Fe)-Sb-Bi sulfosalts from Bazoges and Les Chalanches (France), and Pedra Luz (Portugal), give new data about (Bi, Sb) solid-solution and incorporation of the minor elements Cu, Fe or Ag in jaskolskiite, and in izoklakeite-giessenite and kobellite-tintinaite series. Jaskolskiite from Pedra Luz has high Sb contents (from 17.9 to 20.7 wt.%), leading to the extended general formula: Cu _x Pb_2+x (Sb_1–y Bi _y )_2–x S₅, with 0.10 x 0.22 and 0.19 y 0.41. Fe-free, Bi-rich izoklakeite from Bazoges has high Ag contents (up to 2.2 wt. %), leading to the simplified formula Cu₂Pb₂₂Ag₂(Bi, Sb)₂₂S₅₇; in Les Chalanches it contains less Ag content (1.2 wt.%), but has an excess of Cu that gives the formula: Cu_2.00 (Cu_0.49Ag_1.18)_=1.67Pb_22.70(Bi_12.63Sb_8.99)_=21.62S_57.27.In tintinaite from Pedra Luz, the variation of the Fe/Cu ratio can be explained by the substitution: Cu + (Bi, Sb) Fe + Pb; Fe-free kobellite from Les Chalanches has a Cu-excess, corresponding to the formula Cu_2.81Ag_0.54Pb_9.88(Bi_10.37Sb_5.21)_=15.38S_35.09. Eclarite from the type locality, structurally related to kobellite, shows a Cu excess too. In natural samples of the kobellite homologous series, Fe is positively correlated with Pb, and its contents never exceed that of Cu. Ag substitutes for Pb, together with (Bi, Sb). Taking into account the possibility of Cu excess, but excluding formal Cu²⁺ and Fe³⁺, general formulae can be written:  相似文献   

Te-Rich argyrodite occurrence in Roşia Montană ore deposit,Apuseni Mountains,Romania     

Laurent Bailly  Călin-Gabriel Tămaş  Adrian Minuţ 《Comptes Rendus Geoscience》2005,337(8):755-762

A new argyrodite occurrence has been discovered in the Ro?ia Montan? ore deposit located in the South Apuseni Mountains, Romania. Argyrodite is associated with common base metal sulfides and sulfosalts (galena, sphalerite, chalcopyrite, tetrahedrite ± alabandite, pyrite, and marcasite), tellurides (hessite, altaite, sylvanite) and rare electrum grains in the Ag-rich Cârnicel vein hosted by an extracraterial phreatomagmatic breccia within the Cârnic massif. SEM and EPMA analyses revealed that this argyrodite is Te-rich and a mean Ag_8.04Ge_0.9Te_2.07S_3.77 formula was calculated. This phase could be the germaniferous equivalent of the previously-described Te-rich canfieldite. To cite this article: L. Bailly et al., C. R. Geoscience 337 (2005).  相似文献   

New compositional and optical data for antimonian and bismuthian varieties of hemusite from Japan     

Dr. M. Shimizu  Dr. C. J. Stanley  Dr. A. J. Criddle  Dr. A. Kato  Dr. S. Matsubara 《Mineralogy and Petrology》1991,45(1):11-17

Summary New compositional and optical data are reported for antimonian and antimonianbismuthian varieties of hemusite from epithermal Au-Ag-Cu deposits in Japan. The empirical formula for the antimonian variety, from the Iriki mine is: (Cu_5.83Fe_0.14Ag_0.01)_5.98Mo_1.03(Sn_0.54Sb_0.41Te_0.03Bi_0.02)_1.00(S_7.85Se_0.15)_8.00, and that of the Sb-Bi variety from the Kawazu mine is: (Cu_5.84Fe_0.14Ag_0.01)_5.99Mo_1.03(Sn_0.82Sb_0.11Bi_0.l0Te_0.04)_1.07(S_7.80Se_0.12)_7.92. The theoretical formula of hemusite is Cu⁺ ₄Cu²⁺ ₂MO⁴⁺Sn⁴⁺S₈, whilst the most probable formula of the Iriki hemusite is Cu⁺ _4.5CU²⁺ _1.5Mo⁴⁺Sn⁴⁺ _0.5Sb⁵⁺ _0.5S₈, with Sb⁵⁺ substituting for Sn⁴⁺ and forming (SbS₄)^3– tetrahedra as might be expected, given that the metal to sulphur ratio is 1, and given the sphalerite-like structure of the mineral. However Bi³⁺ cannot be so accommodated, resulting in a deficiency in (S + Se) for Kawazu hemusite. Reflectance spectra for both are compared with those of the tungsten analogue (compositional) of hemusite, kiddcreekite. The relationship between hemusitesensu stricto and these newly reported varieties is discussed in terms of simple and coupled chemical substitutions, and inferences are drawn on the valency of Sb, Bi, Mo and Cu in the hemusite structure.

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Neue chemische und optische Daten für antimon- und bismuthführende Varietäten von Hemusit aus Japan

Zusammenfassung Neue chemische und optische Daten für antimon- und bismuthführende Hemusite auf epithermalen Au-Ag-Cu Lagerstätten in Japan werden vorgelegt. Die empirische Formel für die antimon-führende Varietät aus der Iriki-Mine ist: (Cu_5.83Fe_0.14Ag_0.01)_5.98Mo_1.03(Sn_0.54Sb_0.41Te_0.03Bi_0.02)_1.00 (S_7.85Se_0.15)_8.00, und die der Sb-Bi Varietät aus der Kawazu Mine ist: (Cu_5.84Fe_0.14Ag_0.01)_5.99M0_1.03(Sn_0.82Sb_0.11Bi_0.l0Te_0.04)_1.07 (S_7.80Se_0.12)_7.92. Die theoretische Formel von Hemusit ist Cu⁺ ₄Cu²⁺ ₂Mo⁴⁺Sn⁴⁺S₈, während die wahrscheinlichere Formel für den Hemusit von Iriki Cu⁺ ₄Cu²⁺ _1.5Mo⁴⁺Sn⁴⁺ _0.5Sb⁵⁺ _0.5S₈, mit Sb⁵⁺ an der Stelle von Sn⁴⁺, das(SbS₄)^3– Tetraeder bildet, wie zu erwarten ist, unter der Voraussetzung, da das Metall zu Schwefelverhältnis 1 und die Struktur sphaleritähnlich ist. Bi³⁺ kann jedoch nicht in dieser Weise untergebracht werden, und das führt zu einem Mangel an (S + Se) für den Hemusit von Kawazu. Die Reflektions-Spektren beider Minerale werden mit denen des Wolfram-Equivalents von Hemusit (Kiddcreekit) verglichen. Die Beziehung zwischen Hemusitsensu stricto und diesen jetzt beschriebenen Varietäten wird auf der Basis einfacher und gekoppelter chemischer Substitution diskutiert. Auf dieser Basis werden Schlüsse auf die Valenz von Sb, Bi Mo und Cu in der Hemusit-Struktur gezogen.

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Silver and Sulfosalt Minerals in Tungsten Deposits,South China     

梁书艺  夏宏远 《中国地球化学学报》1989,8(2):135-145

Silver occurs in South China wolframited-quartz veins in three forms:(1)as micro inclusions of Ag2S and AgBiS2,(2) as argentite and matildite as a result of exsolution and(3)as Ag-bearing sulfosalts and independent silver minerals.According to mineral assemblaged the Ag-bearing tungsten deposits are classified as two types:(1)Ag-bearing W-Bi deposits in eastern Nanling,where gustavite has been found and（2）Ag-bearing W-Sn(Sb)deposits which are mainly distributed in western Nanling.The authors consider that the enrichment of silver and sulfosalt minerals in the lower parts of pneumato-hypothermal tungsten deposits is the result of reversed vertical zoning caused by high concentrations of F and S in the ore-forming fluids.  相似文献   

The Hiendelaencina mining district (Guadalajara,Spain)     

J. Martínez Frías 《Mineralium Deposita》1992,27(3):206-212

The Hiendelaencina mining district (Guadalajara, Spain), includes the ore deposits of the Hiendelaencina, La Bodera and Congostrina areas. In this paper a general overview of this district is given, with special emphasis on the parageneses, mineralizing stages and chemical characteristics of the sulphides and sulphosalts. These deposits contain silver in Sb-rich sulphosalts such as freibergite, pyrargyrite, polybasite, stephanite, freieslebenite and the Bi-rich sulphosalt, aramayoite. Three mineralizing stages have been detected in Hiendelaencina and Congostrina: (1) As-Fe; (2) Cu-Zn-Fe-Sb-Ag; and (3) Pb-Sb-Ag (±Bi) but only two in La Bodera (stages 2 and 3). The average sulphosalt formulas are: freibergite (Cu_0.5 Ag_5.9) (Fe_1.42 Zn_0.66) (Sb_4.49 As_0.02) S₁₃; pyrargyrite Ag_3.38 Sb_1.0 S₃; polybasite (Ag_16.3Cu_0.15) (Sb_2.8 As_0.15) S₁₁; stephanite Ag_6.7 Sb_1.38 S₄; freieslebenite Ag_1.1 Sb_0.83 Pb_1.05 S₃ and aramayoite Ag_1.06 Bi_{0. 35} Sb_0.7 Pb_0.03 S₂. The compositional patterns of these sulphosalts (mainly based on the Sb/(Sb + Ag), Ag/ (Ag + Cu), Sb(Ag + As) and Ag/(Ag + Cu) ratios) are outlined, pointing broadly to similar tendencies in their chemistry and genetic conditions.  相似文献   

Ag2(S,Se) solid solutions in the ores of the Rogovik gold-silver deposit (northeastern Russia)     

《Russian Geology and Geophysics》2015,56(12):1738-1748

The relationships and chemical compositions of silver sulfoselenides in the ores of the Rogovik gold-silver deposit (northeastern Russia) were studied to refine the low-temperature region of the Ag₂S-Ag₂Se phase diagram and identify contradictions between natural and experimental data. Two types of relationships between the phases of the system Ag₂S-Ag₂Se have been recognized using optical and scanning electron microscopy: (1) Se-acanthite and S-naumannite occur as monomineral microinclusions or fill cracks in the grains or the interstices of other minerals, and acanthite (free of impurities) forms rims on Fe-sphalerite; (2) Se-acanthite forms rims on S-naumannite. Electron probe microanalysis of silver sulfoselenides from the Rogovik ores revealed 0–7.9 wt.% Se in acanthite and 0–3.2 wt.% S in naumannite, which corresponds to the acanthite series Ag₂S-Ag₂S₀.₇₄Se₀.₂₆ and naumannite series Ag₂S₀.₂₈Se₀.₇₂-Ag₂Se. The composition ranges of the studied acanthite and naumannite series are wider than those of natural silver sulfoselenides from the Guanajuato (Mexico), Silver City (USA), Salida (Indonesia), and other deposits (Ag₂S-Ag₂S0.85Se0.₁5 and Ag₂S0.₁₂Se0.88-Ag₂Se, respectively) but are significantly narrower than the composition ranges of synthetic samples: Ag₂S-Ag₂S0.₄Se0.6 and Ag₂S0.3Se0.₇-Ag₂Se. The presence of intergrowths of two phases of the Ag₂S-Ag₂Se series in the form of Se-acanthite rims on S-naumannite in the Rogovik ores and the absence of three-phase intergrowths of silver sulfoselenides Ag₂S_1 -xSe_x from this and other deposits do not confirm the assumption on the existence of the third solid solution. The results of earlier studies of natural Ag₂(S,Se) solid solutions show the existence of two solid solutions (of the acanthite and naumannite series) in the Ag₂S-Ag₂Se system and confirm the experimental data. It is necessary to carry out a detailed examination of natural silver sulfoselenides falling in the interval from Ag2S0.4Se0.6 to Ag2S0.3Se0.7 in order to identify the limits of two-phase immiscibility.  相似文献   

Distribution of gold and silver and its relation with hypogene ore minerals in the Esperanza porphyry deposit,Antofagasta Region,Chile     

Shoji Kojima  María Constanza San Martín  Toshiro Nagase  Daisuke Nakashima  Claudio Bisso  Andrew Menzies 《Resource Geology》2021,71(1):80-90

Modes of occurrence of Au‐ and Ag‐bearing phases and their relation with associated hypogene ore minerals were examined with the objective to elucidate Au‐Ag distribution at the Esperanza porphyry deposit in the Eocene Centinela copper belt, using ore‐microscope modal analysis, semi‐quantitative analyses by automated mineralogy, electron probe microanalysis, and secondary ion mass spectrometer. The Esperanza hypogene mineralization is characterized by early‐stage chalcopyrite‐rich veinlets in the potassic alteration zone and later polymetallic stage with tennantite and galena in the chlorite‐sericitic alteration zone. Only the early‐stage chalcopyrite contains fine‐grained electrum (Au₆₈Ag₃₂ ‐ Au₈₁Ag₁₉) and hessite (Ag₂Te), and thus yields positive correlations in Cu vs. Au and Cu vs. Ag grades that are clearly recognized in the hypogene sulfide zone. The early‐stage chalcopyrite grains frequently exhibit polysynthetic twinning suggestive of inversion from intermediate solid solution. These features suggest that the fine‐grained electrum and hessite are products exsolved in the cooling process with the intermediate solid solution to chalcopyrite inversion. In contrast, tennantite and galena of the later‐stage mineralization contain no detectable Ag, and it is thus proposed that the early‐stage inverted chalcopyrite is the principal storage of economically important precious metals.  相似文献   

Geology, Mineralogy, and Formation Environment of the Disseminated Gold-Silver Telluride Bulawan Deposit, Negros Occidental, Philippines     

Victor B. MAGLAMBAYAN  †  Daizo ISHIYAMA  Toshio MIZUTA  Akira IMAI  Yohei ISHIKAWA 《Resource Geology》1998,48(2):87-104

Abstract: The Bulawan deposit is located in the porphyry copper belt of southwest Negros island, Philippines. Propylitic, K–feldspar, sericitic, and carbonate alteration types can be distinguished in the deposit. Propylite alteration occurs mainly in Cretaceous-Eocene andesitic lavas and agglomerates while K–feldspar, sericite and carbonate alteration types occur mostly in the Middle Miocene dacite porphyry breccia pipes and stocks which were intruded into the andesites. K-feldspar zones occur in the inner parts of the sericitized zone. Sericite alteration overprinted the propylitized and K-feldspar alteration zones, at lower temperature than epidote and chlorite in the propylitized zone. Carbonate alteration is associated with the mineralization in the center of the breccia pipes and along faults. Mineralization consists of gold-silver telluride ores that are hosted by the carbonate– and sericite-altered dacite porphyry breccia pipes. The Bulawan ores occur mainly as disseminations, but unlike many epithermal gold deposits, lack classical epithermal colloform and crustiform quartz veins. The ore minerals are sphalerite, galena, chalcopyrite, pyrite and tetrahedite-tennantite with minor amounts of electrum, calaverite, petzite, sylvanite, hessite, tellurobismuthite, coloradoite, altaite, and rucklidgeite. Electrum and telluride minerals are associated mostly with calcite and dolomite-ankerite minerals. Fluid inclusions in quartz and calcite in clasts of propylitized andesite in the breccia pipes homogenize from about 300° to 400°C while fluid inclusions in quartz, calcite and sphalerite within the dacite porphyry breccia pipes homogenize between 300° to 310°C. The ores were formed around 300°C from hydrothermal solutions with salinity of about 6. 6 wt % NaCl equivalent. The presence of sylvanite and calaverite as intergrowths with each other, and the Ag content of calaverite are consistent with the above temperature estimate. Based on paragenesis, the Bulawan deposit formed in a pyrite-stable environment, with pH between 3. 4 and 5. 5, f_O2 between 10^-32 to 10^-30 atm, f_S2 between 10^-9.8 to 10^-7.8 atm, f_Te2 between 10^-8.9 to 10^-6.5 atm, and total sulfur content about 10^-2.8 molal. The dominant reduced sulfur species in the ore solutions may have been H₂S_(aq), and the likely aqueous tellurium species were H₂Te_(aq) and H₂TeO_3(aq). The ore minerals in the Bulawan deposit were probably formed by mixing of slightly saline and low salinity fluids.  相似文献   

Phase relations in the systems Ag2S-Cu2S-PbS and Ag2S-Cu2S-Bi2S3 and their mineral assemblages     

Wu Daqing 《中国地球化学学报》1987,6(3):216-224

Phase relations in the ternary systems Ag₂S-Cu₂S-PbS and Ag₂S-Cu₂S-Bi₂S₃ were studied using the silica vacuum technique. In the system Ag₂S-Cu₂S-Bi₂S₃ the phase relations are dominated by join-lines from galena to f.c.c. (Ag_x Cu_2−xS) and b.c.c. (Cu_x Ag_2−xS) at 500°C. With decreasing temperature, galena can coexist with all the phases on the Ag₂S-Cu₂S join. There are six solid solutions, and one new phase, i.e., “C” whose composition is Ag_1.1 Cu_4.8Bi_5.8S₁₂ in the system Ag₂S-Cu₂S-Bi₂S₃ at 500°C. The pavonite (AgBi₃S₅) contains 14 mole% Cu₂S in solid solution, but only 3.0 mole% Ag₂S in CuBi₃S₅ solid solution. The Cu₃Bi₅S₉ ss and wittichenite (Cu₃BiS₃) ss can form join-lines with pavonite as and have the maximum contents of 9.0 and 18 mole% Ag₂S. The most striking feature is the presence of bejaminite as a stable phase with a chemical formula of Ag₂Bi₄S₇ on the Ag₂S-Bi₂S₃ join. AgBiS₂ of the PbS type occupies a fairly large field with a maximum of 23 mole% Cu₂S.  相似文献   

Experimental investigation of the Ag-TI-Bi-Sb-S system     

Prof. Dr. I. Grzetić  G. Moh 《Mineralogy and Petrology》1995,53(4):251-263

Summary Polymetallic ore deposits of low temperature origin often contain thallium as a minor element. By means of modern analytical methods numerous new T1 minerals are described, but their coexistence and equilibria are not investigated yet.The equilibria at 200°C of the quasi-quaternary system Ag₂S-Tl₂S-Sb₂-Sb₂S₃-Bi₂S₃ and the corresponding subsystems were studied. The system Ag₂S-Tl₂S-Sb₂S₃-Bi₂S₃ contains only one quasiquaternary phase, AgTlSbBiS₄, which is connected by tie-lines with all quasiternary phases in the system (Ag₄Sb₃BiS₈ and Ag₃Tl₃Sb₂S₆) and with most quasibinary phases: SbBiS₃, weissbergite (TlSbS₂), (TlBiS₂, pyrargyrite (Ag₃SbS₃), miargyrite (AgSbS₂) and matildite (AgBiS₂). This phase diagram makes it possible to investigate all important naturally occurring parageneses of Ag and Tl sulphosalts containing Sb and Bi.

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Die experimentelle Untersuchung des Ag-TI-Sb-Bi-S Systems

Zusammenfassung In polymetallischen Sulfiderzen niedriger Bildungstemperaturen sind Spuren von Thallium fast immer nachweisbar. In jüngster Zeit wurde mittels moderner Analysentechniken eine Reihe neuer Thalliumminerale entdeckt, charakteristische Paragenesen sind bisher und Phasengleichgewichte jedoch unerforscht.In einer experimentellen Studie wurde das quasi-quaternäre System Argentit (Ag₂S)-Carlinit (Tl₂S)-Antimonglanz (Sb₂S₃)-Wismutglanz (Bi₂S₃) bei 200 °C untersucht. Es enthält nur eine quasi-quaternäre Phase AgTlSbBiS₄, welche durch Konoden mit den quasi-ternären Phasen Ag₄Sb₃BiS₈ und Ag₃Tl₃Sb₂S₆, sowie mit den quasi-binären Phasen Pyrargyrit (Ag₃SbS₃), Miargyrit (AgSbS₂), Schapbachit (Matildit, AgBiS₂), Weissbergit (TlSbS₂), TlBiS₂ und SbBiS₃ verknüpft ist. Das vorliegende Phasendiagramm ermöglichtes die Phasenbeziehungen natürlich vorkommender Ag- und Tl-Sulfosalze, die Sb und Bi enthallen, darzustellen.

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With 5 Figures

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Deceased  相似文献   

Betekhtinite and bi-sulfosalts from the copper mine of „La Leona“ (Argentina)     

Beatriz Melba Honnorez-Guerstein 《Mineralium Deposita》1971,6(2):111-121

The copper deposit La Leona consists of ore veins in a granite batholite which intruded into Permian sediments. In these veins the following minerals are observed: pyrite, sphalerite, chalcopyrite, galena, betekhtinite, two Bisulfosalts, electrum, bornite, chalcocite, enargite, tennantite, Zn-Fahlerz, cuprite, delafossite, molybdenite, hematite and iron hydroxides, and copper carbonates with quartz and iron carbonates as gangue. The betekhtinite, (CuFe)₁₀Pb S₆, found for the first time in Argentina, the Zn-Fahlerz and the sulfosalts (Cu_3.2Bi_1.2Pb_1.2S_8.5) and (Cu_9.3Bi_1.1S_6.8) were studied in detail under the microscope, by X-rays and by microprobe. Specifically, the paragenesis of these three minerals with galena, chalcocite and bornite is discussed.

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Résumé Le gisement de cuivre de la mine «La Leona» est formé de filons de minerais recoupant un batholite granitique qui a fait intrusion dans des sédiments permiens. Les minéraus suivants ont été observés: pyrite, blende, chalcopyrite, galène, bétekhtinite, deux sulfosels de Bi, électrum, bornite, chalcosine, énargite, tennantite, «Zn-Fahlerz», cuprite, delafossite, molybdénite, hématite et hydroxydes de fer, des carbonates de cuivre, dans une gangue de quartz et de carbonates de fer. La bétekhtinite (Cu Fe)₁₀Pb S₆, trouvée pour la première fois en Argentine, le «Zn-Fahlerz» et les sulfosels (Cu_3.2Bi_1.2Pb_1.2S_8.5) et (Cu_9.3Bi_1.1S_6.8) ont été spécialement étudiés à l'aide de la microscopie, de la diffraction des rayons-X et de la microsonde. La paragénèse formée par ces trois mineraux associés à la galène, la chalcosine et la bornite est discutée.

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鄂东南鸡笼山矽卡岩型金铜矿床金、银、碲、铋的赋存状态及其对成矿条件的制约   总被引：1，自引：0，他引：1  

韩颖霄  谢桂青 《岩石矿物学杂志》2016,35(4):655-676

鸡笼山矽卡岩型金铜矿床是长江中下游成矿带典型的矽卡岩矿床,矿体主要赋存于下三叠统大冶组碳酸盐岩与花岗闪长斑岩接触带内。根据野外观察和镜下鉴定,将成矿过程划分为进矽卡岩阶段、退化蚀变阶段、石英-硫化物阶段和碳酸盐阶段,其中石英-硫化物阶段为金和铜的主要成矿阶段。鸡笼山金铜矿床中不同类型矿石的矿相学观察和电子探针微区成分分析(EPMA)表明,金、银主要以自然金、银金矿、碲银矿、硫银铋矿等形式产出,主要载金矿物为黄铜矿和黄铁矿;同时发现鸡笼山金铜矿床中发育大量碲-铋矿物(如辉碲铋矿、针硫铋铅矿等)。成矿流体物理化学性质研究表明,鸡笼山金铜矿床中金银元素在高温热液中主要以氯络合物的形式运移,随着温度降低和流体进一步的演化,金银元素转变为以硫络合物、碲铋化物熔体等形式运移。在石英-硫化物阶段,由于硫化作用与流体的沸腾作用,流体中硫逸度降低,碲逸度升高;当流体处于黄铁矿-磁黄铁矿氧逸度范围、酸碱性呈中性-弱碱性、碲逸度(logf_(Te2))为-10.7~-8.4、硫逸度(logf_(S_2))为-11.4~-10.6时,金、银、铜元素近于同时沉淀,碲、铋和砷元素对金和银元素运移和富集起到了重要作用,最终形成了鸡笼山矽卡岩型金铜矿床。  相似文献   

Fe-rich Li-bearing magnesionigerite-6N6S from Xianghualing tin-polymetallic orefield, Hunan Province, P.R. China     

Zhuming Yang  Kuishou Ding  Jeffrey de Fourestier  Qian Mao  He Li 《Mineralogy and Petrology》2013,107(2):163-169

The Fe-rich Li-bearing magnesionigerite-6N6S occurs in the Xianghualing tin-polymetallic ore field, Linwu County, Hunan Province, Peoples Republic of China. It was found near the outer contact zone of the Laizhiling granite body and in the Middle-Upper Devonian carbonate rocks of Qiziqiao Formation. The mineral formed during the skarn stage. Its empirical formula is Sn_1.81Li_0.67(Fe_1.43Zn_1.19 Mn_0.41)_Σ3.03(Al_14.89Mg_1.46 Ti_0.11Si_0.01)_Σ16.47O₃₀(OH)₂. The structure for magnesionigerite-6N6S was solved and refined in space group R-3?m, with a?=?5.7144(8), c?=?55.446(11) Å, V?=?1568.0(4) ų, to R1?=?0.0528. Based on the structural refinement of single crystal diffraction data the formula of magnesionigerite-6N6S is Sn_1.80Li_0.97(Fe_1.89Zn_0.91) _Σ2.80 (Al_14.60Mg_1.63 Ti_0.20)_Σ16.43O₃₀(OH)₂ with Z?=?3. Fe-rich Li-bearing magnesionigerite-6N6S contains 0.74 wt.% Li₂O. The idealized charge-balanced composition of magnesionigerite-6N6S may be expressed by bivalent and trivalent cations: (Mg²⁺)₄(Al³⁺)₁₈O₃₀(OH)₂. The simplified general formula for the 6N6S polysomes in the nigerite and högbomite groups can be given as A _x B_18-x O₃₀(OH)₂, x?=?~4, where A?=?Mg²⁺, Fe²⁺, Zn²⁺; B?=?Al³⁺, Sn⁴⁺, Ti⁴⁺, Li⁺, □.  相似文献   

Determination of the thermodynamic properties of compounds in the Ag-Au-Se and Ag-Au-Te systems by the EMF method     

E. A. Echmaeva  E. G. Osadchii 《Geology of Ore Deposits》2009,51(3):247-258

The standard thermodynamic properties (Δ_f G°, S°, Δ_f H°) of the following synthetic minerals and compounds in the Ag-Au-Se and Ag-Au-Te systems were determined by the EMF method: β-Ag₂Se (low-temperature naumannite), α-Ag₂Se (high-temperature naumannite), Ag₃AuSe₂ (fischesserite), AuSe, Ag₅Te₃ (stützite), Ag₂ Te (hessite), and Ag₃AuTe₂ (petzite). All minerals and compounds were produced by solid-phase synthesis from elements or electrum of the given composition in evacuated ampoules made of quartz glass. The phases were verified by X-ray diffraction analysis, microscopically in reflected light, and with an electron microprobe. The absence of the ternary compound AgAuSe in the Ag-Au-Se system was confirmed by solid-phase annealing. On the basis of experimental data on the electromotive force E versus temperature, the equations E(T) were calculated, from which the temperature-dependent relationships of the Gibbs energy in the relevant reactions and the standard thermodynamic functions of compounds within the range 300–502 K were obtained.  相似文献   

Jinshanjiangite and bafertisite from the Gremyakha-Vyrmes Alkaline Complex,Kola Peninsula     

I. S. Lykova  I. V. Pekov  N. N. Kononkova  A. K. Shpachenko 《Geology of Ore Deposits》2010,52(8):837-842

Jinshanjiangite (acicular crystals up to 2 mm in length) and bafertisite (lamellar crystals up to 3 × 4 mm in size) have been found in alkali granite pegmatite of the Gremyakha-Vyrmes Complex, Kola Peninsula. Albite, microcline, quartz, arfvedsonite, zircon, and apatite are associated minerals. The dimensions of a monoclinic unit cell of jinshanjiangite and bafertisite are: a = 10.72(2), b=13.80(2), c = 20.94(6) Å, β = 97.0(5)° and a = 10.654(6), b = 13.724(6), c = 10.863(8) Å, β = 94.47(8)°, respectively. The typical compositions (electron microprobe data) of jinshanjiangite and bafertisite are: (Na_0.57Ca_0.44)_Σ1.01(Ba_0.57K_0.44)_Σ1.01 (Fe_3.53Mn_0.30Mg_0.04Zn_0.01)_Σ3.88(Ti_1.97Nb_0.06Zr_0.01)_Σ2.04(Si_3.97Al_0.03O₁₄)O_2.00(OH_2.25F_0.73O_0.02)_Σ3.00 and (Ba_1.98Na_0.04K_0.03)_Σ2.05(Fe_3.43Mn_0.37Mg_0.03)_Σ3.83(Ti_2.02Nb_0.03)_Σ2.05 (Si_3.92Al_0.08O₁₄)(O_1.84OH_0.16)_Σ2.00(OH_2.39F_1.61)_Σ3.00, respectively. The minerals studied are the Fe-richest members of the bafertisite structural family.  相似文献