The sheltered environment of the Algares +30 level adit (underground mine gallery) contributes to preservation secondary water-soluble minerals formed on tunnel walls. massive sulphide and related stockwork zone are hosted by Mine Tuff volcanic unit exposed in walls gallery, showing intense oxidation hydrothermal alteration. Minerals from halotrichite group were identified efflorescent salts, t...

Past waste disposal practices have left large volumes of sulphidic material stockpiled in a Ramsar wetland site on the Atlantic coast southwestern Spain, leading to severe land degradation. With aim addressing this legacy issue, soil core samples were collected along two transects extending from abandoned stockpiles adjacent marshland and subjected XRD, SEM-EDS, ICP-OES ICP-MS analyses. Sulphid...

when organic material is decomposed under oxygen-limiting conditions (Nedwell, 1982). (The term sulphide is intended to include undissociated H2S, the bisulphide anion HS− and the sulphide anion S2−.) In marine sediments, sulphide production is enhanced by bacterial sulphate reduction (Jorgensen and Fenchel, 1974; Nedwell, 1982). Species inhabiting intertidal flats or salt marshes are, therefor...

The influence of microwave heating on the leaching kinetics of chalcopyrite and sphalerite has been investigated. Chalcopyrite is inert to many leaching agents, especially ferric ion media. This mineral is considered to be one of the largest sources of copper, in terms of the scale of availability, and copper is usually extracted by pyrometallurgical processes. However, there has recently been ...

Bioleaching and biogenesis are the main outputs from a large group of environmental processes participating in the natural material cycle, used in raw materials processing. Bio-oxidation reactions are the main basis for bioleaching procedures, often participating in parallel leaching processes. During the leaching processes of polycomponent sulphide substrates, the factor of process selection a...

BACKGROUND Hydrogen sulphide is a gas signalling molecule which is produced endogenously from L-cysteine via the enzymes cystathionine beta-synthase (CBS) and cystathionine gamma-lyase (CSE). The possible role of hydrogen sulphide in reproduction has not yet been fully investigated. It has been previously demonstrated that hydrogen sulphide relaxes uterine smooth muscle in vitro. The aim of the...

In the Dusina area, which is built up of Lower Palaeozoic metasediments, Devonian carbonate complex and Upper Palaeozoic metarhyolites unconformably overlain by Upper Permian sediments, numerous ore occurrences have been investigated: (a) "stratabound" metamorphic hematite deposits in the pre-Devonian metasediments; (b) epigenetic veins and pipes of barite (& calcite) with accessory Hg-tetrahed...

The discovery of a natural quasicrystal, icosahedrite (Al63Cu24Fe13), accompanied by khatyrkite (CuAl2) and cupalite (CuAl) in the CV3 carbonaceous chondrite Khatyrka has posed a mystery as to what extraterrestrial processes led to the formation and preservation of these metal alloys. Here we present a range of evidence, including the discovery of high-pressure phases never observed before in a...

Hydrothermal chimneys and compartments comprising transition metal sulphides and associated minerals have been proposed as likely locations for the beginnings of life. In laboratory simulations of off-axis alkaline springs, it is shown that the interaction of a simulated alkaline sulphide-bearing submarine vent solution with a primeval anoxic iron-bearing ocean leads to the formation of chimney...

The McLymont property is located close to the headwaters of McLymont Creek, a tributary of the lskut River; it lies at an elevation of approximately I I70 metres (3800 feet), about 2 kilometres southwest of Newmont Lake (Figure 2-l I-l) The property is currently being explored by Gulf International Minerals Ltd. It contains two styles of mineralization whose relationship to each other is uncert...