scholarly journals Sodium Chemical Sources of Current with Cathods Based on Copper Sulphides

2019 ◽  
Vol 11 (4) ◽  
pp. 85-92
Author(s):  
D.C. Linnik ◽  
◽  
T.B. Polishchuk ◽  
V.A. Glazunova ◽  
D.A. Zherebtsov ◽  
...  
Keyword(s):  
Copper Sulphides

Mechanochemical transformations and reactivity in copper sulphides

2003 ◽  
Vol 64 (8) ◽  
pp. 1413-1417 ◽  
Author(s):  
P Baláž ◽  
L Takacs ◽  
E Boldižárová ◽  
E Godočı́ková
Keyword(s):  
Copper Sulphides

scholarly journals Microstructural characterisation of a collection of Protohistoric bronzes

2013 ◽  
Vol 19 (S4) ◽  
pp. 109-110
Author(s):  
E. Figueiredo ◽  
R.J.C. Silva ◽  
M.F. Araújo ◽  
R. Vilaça
Keyword(s):  
Tin Oxide ◽  
Research Work ◽  
Dendritic Structure ◽  
Polarized Light ◽  
Metallic Matrix ◽  
Surface Finishing ◽  
Internal Corrosion ◽  
Small Areas ◽  
Microstructural Characterisation ◽  
Copper Sulphides

Microstructural characterisation of an archaeological collection of Protohistoric bronze artefacts attributed to around the VIII century B.C. and has been carried out using optical microscopy (OM) and scanning electron microscopy combined with energy dispersive spectroscopy (SEM-EDS). The collection was found in Medronhal cave (Condeixa-a-Nova, Portugal) and is composed by 1 fibula, 5 bracelets and 31 rings.Small areas on the surfaces of the artefacts were cleaned from corrosion and were metallographically prepared by a manual polishing with several diamond suspensions in a cotton swab until 1 micron diamond size. OM observations were performed in bright field (BF) illumination and under polarized light (Pol), in unetched and etched conditions. SEM-EDS was performed without a conductive coating for a minimum external elemental interference.OM observations allowed the study of the method and sequence of manufacture involved in the production of the various types of artefacts. Results show that the fibula and the bracelets have equiaxed (recrystallised) grain structures resulting from cyclic thermo-mechanical treatments performed to a pre-form cast bar until requested shape and surface finishing was attained. The rings, which are of diverse sizes, have various types of microstructures as a result of diverse manufacturing techniques. Some show a dendritic structure that resulted from the casting, and others show recrystallised structures that resulted from cycles of deformation and annealing procedures posterior to their casting (Figure 1).SEM-EDS analysis allowed the study of the presence of inclusions in the metallic matrix and the study of corrosion in some artefacts (Figure 2). Different types of inclusions were identified, namely copper sulphides, tin oxide, and lead rich inclusions. Both copper sulphides and lead inclusions are commonly found in archaeological bronzes, and can be a result of copper ores impurities. Tin oxide, on the other hand, is not so common, and its presence can be understood as a result of preferential oxidation of tin regarding copper during a melting or alloying operation. The study of the interface alloy/corrosion showed the presence of chlorides in internal corrosion layers, which can probably be related to an aggressiveness of the burial environment.This research work has been financed by the Portuguese Science Foundation (FCT) through the EarlyMetal project (PTDC/HIS-ARQ/110442/2008), the grant SFRH/BPD/73245/2010 (to EF) and the Strategic Project-LA25-2011-2012 (PEst-C/CTM/LA0025/2011) (to CENIMAT/I3N).

scholarly journals Copper-Containing Agates of the Avacha Bay (Eastern Kamchatka, Russia)

Minerals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1124
Author(s):  
Galina Palyanova ◽  
Evgeny Sidorov ◽  
Andrey Borovikov ◽  
Yurii Seryotkin
Keyword(s):  
Raman Spectroscopy ◽  
Powder Diffraction ◽  
Fluid Inclusions ◽  
Silica Matrix ◽  
Native Copper ◽  
X Ray ◽  
Eastern Kamchatka ◽  
Copper Mineralization ◽  
Avacha Bay ◽  
Copper Sulphides

The copper-containing agates of the Avacha Bay (Eastern Kamchatka, Russia) have been investigated in this study. Optical microscopy, scanning electron microscopy, electron microprobe analysis, X-ray powder diffraction, Raman spectroscopy, and fluid inclusions were used to investigate the samples. It was found that copper mineralization in agates is represented by native copper, copper sulphides (chalcocite, djurleite, digenite, anilite, yarrowite, rarely chalcopyrite) and cuprite. In addition to copper minerals, sphalerite and native silver were also found in the agates. Native copper is localized in a siliceous matrix in the form of inclusions usually less than 100 microns in size—rarely up to 1 mm—forming dendrites and crystals of a cubic system. Copper sulphides are found in the interstices of chalcedony often cementing the marginal parts of spherule aggregates of silica. In addition, they fill the micro veins, which occupy a cross-cutting position with respect to the concentric bands of chalcedony. The idiomorphic appearance of native copper crystals and clear boundaries with the silica matrix suggest their simultaneous crystallization. Copper sulphides, cuprite, and barite micro veins indicate a later deposition. Raman spectroscopy and X-ray powder diffraction results demonstrated that the Avacha Bay agates contained cristobalite in addition to quartz and moganite. The fluid inclusions study shows that the crystalline quartz in the center of the nodule in agates was formed with the participation of solutions containing a very low salt concentration (<0.3 wt.% NaCl equivalent) at the temperature range 110–50 °C and below. The main salt components were CaCl2 and NaCl, with a probable admixture of MgCl2. The copper mineralization in the agates of the Avacha Bay established in the volcanic strata can serve as a direct sign of their metallogenic specialization.

Leaching of Copper Sulphides and Copper Mattes in Oxygenated Chloride/Sulphate Leachants

1992 ◽  
Vol 8 (1-4) ◽  
pp. 183-203 ◽  
Author(s):  
FRANK LAWSON ◽  
CHU-YONG CHENG ◽  
LISA SIEW YING LEE
Keyword(s):  
Copper Sulphides
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