Fleet, M.E., Mumin, A.H. (1997) Gold-bearing arsenian pyrite and marcasite and arsenopyrite from Carlin-trend gold deposits and laboratory synthesis. American Mineralogist: 82: 182-193. Maddox, L.M. et al. (1998) Invisible gold: Comparison of Au deposition on pyrite and arsenopyrite.Web

A multidisciplinary approach has been used to study Au occurrences within pyrite and arsenopyrite in four refractory Au ores from Colombia, France (Le Châtelet and Villeranges) and Portugal (Neves Norte).Web

We consider three principal scenarios of the relations of arsenian pyrite and arsenopyrite: (A) Pyrite with high As content is stable in equilibrium with arsenopyrite. …Web

We suggest that invisible gold in arsenian pyrite and marcasite and arsenopyrite from sediment-hosted gold deposits represents Au removed from ore fluids …Web

Ore mineralogy is characterized by a complex paragenesis of pyrite, arsenopyrite, galena, sphalerite, chalcopyrite, and gold. Gold occurs mostly as electrum in equilibrium with base metals sulfides filling fractures of pyrite and arsenopyrite. ... Fleet ME (1989) Oscillatory-zoned As-bearing pyrite from strata-bound and stratiform gold …Web

Gold-bearing arsenian pyrite and marcasite and arsenopyrite from Carlin Trend gold deposits and laboratory synthesis. Abstract Invisible gold in natural and synthetic arsenian pyrite and marcasite correlates with anomalous As content and Fe deficiency, and high contents of invisible gold in most natural and all….Web

Biooxidation of gold-bearing arsenopyrite concentrates, using acidophilic microbial communities, is among the largest commercial biohydrometallurgical processes. However, molecular mechanisms of microbial responses to sulfide raw materials have not been widely studied. The goal of this research was to gain insight into the defense …Web

The Jinya Au deposit is a typical Carlin-type deposit in the Golden Triangle of Yunnan, Guizhou, and Guangxi provinces, China. The ore bodies occur in the Middle Triassic Baifeng Formation, which are turbidites deposited on the edge of a carbonate platform. The main Au-bearing minerals are arsenopyrite and pyrite, and previous …Web

Pyrite-mediated arsenopyrite oxidation is an important process affecting arsenic (As) mobility. The iron sulfides-induced reactive oxidation species (ROS) can exert significant influence on As transformation. However, the impact of pyrite-arsenopyrite association on ROS production and its contribution to As transformation were rarely …Web

Pyrite Arsenopyrite: Biooxidation tank reactors (Rawlings et al., 2003) Chuquicamata, Chile (planned) ... High level arsenic resistance in bacteria present in biooxidation tanks used to treat gold-bearing arsenopyrite concentrates: a review. Trans. Nonferr. Met. Soc. China, 18 (6) (2008), pp. 1311-1318.Web

Au speciation in sulfides (including "invisible" Au), which mostly controls the loss of Au during ore dressing, is discussed. Modern methods of analysis of Au speciation, with discussion of limitations by locality and sensitivity, are reviewed. The results of sulfide investigation by the methods of scanning and transmission electron microscopy, mass …Web

The chemical composition of various pyrites and arsenopyrites from gold-bearing quartz veins, disseminated pyrite-arsenopyrite-sericite-quartz mineralized slate with different orientation and intense mineralized breccia were determined by LA-ICPMS on a suite of 8 representative samples (Table 1).Web

A pressure oxidation procedure that has gained commercial status for treating gold-bearing arsenopyrite or pyrite employs sulfuric acid (H2SO4) and oxygen as reagents. High temperatures (170° to 190° C) and pressures (up to 400 psig O2) are required to achieve complete oxidation of the sulfide minerals. The chemistry of these …Web

Abstract. A multidisciplinary approach has been used to study Au occurrences within pyrite and arsenopyrite in four refractory Au ores from Colombia, France (Le …Web

Pyrite is another common gold-bearing mineral and often intergrown with arsenopyrite [11]. The effect of pyrite on leaching of arsenopyrite cannot be ignored. According to the measured rest potentials of sulfide minerals [12], the rest potential of arsenopyrite is lower than that of pyrite.Web

What is Arsenopyrite? Arsenopyrite is an iron arsenic sulfide with a chemical composition of FeAsS. It is the most abundant arsenic-bearing mineral and the primary ore of arsenic metal.It is associated with other sulfide minerals in organic-rich sedimentary rocks, metamorphic rocks, and igneous rocks in many parts of the world.. In addition to being …Web

Arsenopyrite and pyrite are the most common Au-bearing minerals in various Au deposits (Large et al., 2007;Bi et al., 2011;Cook et al., 2013). Major and trace elements in arsenopyrite and pyrite ...Web

Notwithstanding, in the separation of gold bearing sulphides during froth flotation, a concentrate made up of both pyrite and arsenopyrite is obtained due to their similar characteristics and ...Web

The formation of arsenic-bearing acid mine drainage (AMD) via the oxidation of arsenopyrite refuse ore has attracted significant attention. Pyrite, as main a concomitant mineral, is a crucial factor that affects the (bio)dissolution of arsenopyrite, but there are still some points on the detailed action mechanism under normal environmental conditions …Web

All types of arsenopyrite contain gold (1250–3000 ppm) and other trace elements such as Cu (200–1300 ppm), Sb (up to 9000 ppm) and Tl (3000–4500 ppm). …Web

arsenopyrite and pyrite as the major sulphide minerals. The ABA confirmed that the gold sulphide ore could be a potential source of AMD with respect to AMD marginal of safety if the ore is left ...Web

The localized presence of narrow, pyrite-arsenopyrite-bearing auriferous quartz developed in some southeast-dipping faults suggests that these faults may locally remobilize structures that were active during the formation of main stage Liese quartz veins, but otherwise these structures are post-mineralization in timing, and do not further ...Web

Arsenopyrite Oxidation with Ozone: Stoichiometry and Kinetics. C. Rodríguez-Rodríguez F. Nava-Alonso A. Uribe-Salas. Chemistry, Materials Science. 2018. ABSTRACT When the recovery of precious metals by standard cyanidation is less than 80%, the ore is classified as refractory and needs an oxidizing pretreatment before …Web

Moreover, a slightly negative correlation between the Au and Fe is observed in the compositions of Au-bearing pyrite and arsenopyrite crystals, and the Au/As values are below the solubility limit ...Web

The Gutaishan deposit is a slate-hosted lode Au–Sb deposit in the Xiangzhong Sb–Au metallogenic province, South China. The deposit has a proven reserve of ca. 9 -t gold at an average grade of 13-g/t and contains 2500-t Sb. The deposit represents the product of a complex ore-forming process, comprising four different stages, of which …Web

Activation mechanism of ammonium oxalate with pyrite in the lime system and its response to flotation separation of pyrite from arsenopyrite. Runpeng Liao S. Wen …Web

Metallic minerals are dominated by pyrite, arsenopyrite (Fig. 3 b–g), native gold, and minor sphalerite, galena, chalcopyrite, tetrahedrite and pyrrhotite. Gangue minerals consist mainly of quartz, ankerite, sericite and chlorite. ... Thirty-three pyrite-bearing samples were collected from the drill cores (ZK0304, ZK0703, ZK3502, ZK3507 …Web

Pyrite and arsenopyrite are the two main gold-bearing minerals in the ALRG gold ore. The content of pyrite is 3.47 %, which is high‑sulfur lean‑iron pyrite in this gold ore, and the disseminated particle size is in the range of 0.01–0.2 mm. Arsenopyrite is the main arsenic-bearing mineral with a content of 0.45 %.Web

The ore minerals mainly consist of native gold, pyrite, arsenopyrite, galena, sphalerite, and chalcopyrite, and the gangue minerals comprise quartz, calcite, albite, ankerite, chlorite, epidote, and sericite. ... The middle-stage Py2c is also an important gold-bearing pyrite type, as its Au content ranges from 0.18 to 18.0 ppm, with a median of ...Web

Pyrite has up to 0.12 wt.% Au, and arsenopyrite contains up to 0.17 wt.% Au. The antithetic correlation between S and As indicates the substitution of As for S in pyrite, and arsenic occurs in anionic As 1− state in the pyrite structure under the reduced conditions. Pyrite has relatively high Co (~364–2248 ppm) but relatively low Ni (~109 ...Web

Later, after particular dissolution of pyrite-1, Au-rich As-bearing pyrite-2 and arsenopyrite precipitated. These facts suggest a marked increase in the arsenic and gold activities in ore-bearing fluids. The As-content of pyrite-2 decreases in an oscillatory manner from the core to the rim, reflecting changes in the As activity or/and in the P ...Web

In both lithologies, euhedral pyrite and arsenopyrite coexist with quartz and ankerite, but chalcopyrite, galena, sphalerite and others are also present, to a lesser extent. Download : Download high-res image (1MB) Download : Download full-size image; ... the sulfur isotopic characteristics of gold-bearing pyrite, and paucity of regional ...Web

Arsenian pyrite and/or arsenopyrite are the dominant Au-bearing minerals. Gold-bearing pyrite grains are typically zoned (core, intermediate, and rim), with multiple, oscillatory banded sub-zones. In situ analysis demonstrates that invisible Au exists mainly as cationic Au + in the growth zones of pyrite.Web

Effect of Au status on ion emission rate Comparison with EMPA analyses The SIMS depth profiles of pyrite and arsenopyrite Au-bearing grains (Fig. 7) show that the first Figure 9 shows grade profiles obtained by SIMS mineral layers enhance Au emission during the Au and EMPA analysis, superimposed for compar- SIMS analysis: steady state is ...Web

The arsenopyrite and pyrite are the main objects for analytical study of gold-bearing sulfide minerals, their different textures, morphology of the crystals and aggregates. The studies of ore...Web

Pyrite and arsenopyrite occur as ten and four texturally distinct subtypes; all host invisible gold, which is lattice-bound. ... change, rele asing of T e and formatio n of T e-bearing mine rals ...Web

Bio-oxidation of a high-sulfur and high-arsenic refractory gold concentrate using a two-stage process. Zhong et al. (2013) investigated the chemical oxidation of pyrite under a pulp density of 1% (w/v) with sufficient ferric ion, and the dissolution rate of pyrite reached after 7 d. The research of Iglesias revealed that the dissolution ...Web

Calculated As concentrations in equilibrium with the pyrite–arsenopyrite assemblage in the surficial environment are 0.01–0.1 ppm, similar to groundwater in arsenopyrite-bearing rocks in this study (0.005–0.3 ppm), and these waters may be in chemical equilibrium. Arsenopyrite decomposes in oxidised waters to yield up to 1100 …Web

Trace-element geochemistry of pyrite and arsenopyrite: ore genetic implications for late Archean orogenic gold deposits in southern India. Mineralogy, …Web