Solid-phase products of bacterial oxidation of arsenopyrite
The probable hypotheses of arsenic contamination in groundwater, like the oxidation of Arsenopyrite
and Pyrites and the reduction of Iron Oxyhydroxides, explain the arsenic contamination problem in Bangladesh well.
Small acicular arsenopyrite
crystals occur on the inner surface of the perimorph, and yellow calcite scalenohedrons occur on its outer surface.
The secondary coating extends several microns from the arsenopyrite
grain boundary (Fig.
Mineralisation consists of pyrite and arsenopyrite
, sulphides of zinc and copper, antimonite, silver sulphosalts and native gold.
25-meter sulfide-bearing zone containing pyrite, chalcopyrite and arsenopyrite
as veins, veinlets, disseminations, and breccias in the interval of 111.
Callinex plans to conduct metallurgical testing in calendar Q4 2016 to further define the relationship between gold and arsenopyrite
, as indicated by previous test work completed during the 1980s.
Sample FFSB (Table 1), High grade quartz-sulphide (abundant arsenopyrite
, pyrite, galena) from the dump by the main shaft, assayed 76.
Fine sulphide minerals, including arsenopyrite
, were observed in association with carbonate veining and alteration in the two samples.
The drill hole encountered quartz carbonate veins with arsenopyrite
and pyrite, and the distinctive sericite alteration of the Ben Vein zone was encountered at 114.
In the Terrace Creek system with high gold grades, insufficient arsenopyrite
is formed to encapsulate the gold and hence discrete gold grains have formed in and around the pyrite crystals.
Pyrite or arsenopyrite
is absent or very rare in aquifer sediments from the Bengal Basin (Acharyya et al.