Occurrence of some Ni- and Sn-rich minerals in copper converter slags

AbstractThe chemistry of opaque spinel, delafossite (Cu2O·Fe2O3), cuprite (Cu2O), cassiterite, nickel-olivine (Ni2SiO4), and bunsenite (NiO) from some copper converter slags has been investigated by electron microprobe analysis. The spinel has a complex composition containing up to 33.89% NiO and 47.69% SnO2, ranging from essentially Ni2SnO4 to (Ni,Fe2+)O4. The associated delafossite contains up to 19.18% NiO and 38.15% SnO2. The chemical variation of the mineral phases is evaluated, and it appears that Ni2+ enters the spinel and delafossite to charge-balance the octahedrally coordinated Sn4+.

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Nature of dioctahedral micas in Spanish red soils

Clay Minerals ◽

10.1180/claymin.1997.032.1.12 ◽

1997 ◽

Vol 32 (1) ◽

pp. 107-121 ◽

Cited By ~ 10

Author(s):

J. M. Martin-Garcia ◽

G. Delgado ◽

M. Sanchez-Maranon ◽

J. F. Parraga ◽

R. Delgado

Keyword(s):

Powder Diffraction ◽

Electron Microprobe ◽

Microprobe Analysis ◽

Electron Microprobe Analysis ◽

X Ray ◽

Red Soils ◽

Mineral Phases ◽

Composition And Structure ◽

Structural Formulae ◽

Coarse Gravel

AbstractStructural formulae and other crystallochemical parameters were used to study different species of dioctahedral micas in clay and coarse gravel fractions of horizons from a red soil (Ultic Haploxeralf) in southern Spain. Mineralogical analyses using X-ray powder diffraction, and measurements of theb0parameter revealed dioctahedral micas, illite and paragonite. Structural formulae established from electron microprobe analysis and energy dispersive X-ray analysis showed the illites to be K mica related in elemental composition and structure to muscovite and phengite. The paragonites were found to be closer to ideal mica. Structural formulae for Na-K dioctahedral micas were obtained with crystallochemical characteristics intermediate between those of Na micas and K micas. The possibilty of these micas representing individual mineral phases or intergrowths of Na and K micas is discussed. In the soil profile, micas from the Bt horizon showed the largest crystallochemical changes induced by pedogenesis.

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Characterization of cation oxidation states in geologic materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100133345 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1742-1743

Author(s):

Anne V. McGuire ◽

M. Darby Dyar

Keyword(s):

Electron Microprobe ◽

Microprobe Analysis ◽

Electron Microprobe Analysis ◽

Iron Oxidation ◽

Oxidation States ◽

Charge Balance ◽

Geologic Materials ◽

Valence States ◽

Treat All ◽

Almost All

One shortfall of electron microprobe analysis is the inability of x-ray spectroscopic methods to distinguish multiple valence states of atoms. In geologic materials, many elements (eg. Fe, Ti, Cr, Mn, Cu, Eu) may exhibit multiple valence states and their quantitative analysis can be important in solving geologic problems. For instance, Fe2+/Fe3+ ratios in minerals may be useful in determining the oxygen fugacities in which rocks equilibrated. In the past, wet chemical methods were generally used to analyze mineral compositions and Fe2+/Fe3+ ratios were routinely determined. The advent of electron microprobe analysis was accompanied by a decrease in determination of iron oxidation states. The modern microprobe analyst generally deals with the inability to measure Fe2+/Fe3+ ratios by picking one of several assumptions: (a) treat all iron as Fe2+; (b) treat all iron as Fe3+; or (c) calculate an Fe2+/Fe3+ ratio using assumptions of perfect mineral stoichiometry and charge balance. Since almost all iron-bearing minerals contain both Fe2+ and Fe3+, the first two treatments are obviously unsatisfactory.

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Scanning Electron Microscopy and Electron Microprobe Analysis of Malignant Cell Cultures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100561 ◽

1968 ◽

Vol 26 ◽

pp. 164-165

Author(s):

R. I. Johnsson-Hegyeli ◽

A. F. Hegyeli ◽

D. K. Landstrom ◽

W. C. Lane

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Cell Cultures ◽

Electron Microprobe ◽

Microprobe Analysis ◽

Electron Microprobe Analysis ◽

Three Dimensional ◽

Malignant Cell ◽

Interference Microscopy ◽

Scanning Electron

Last year we reported on the use of reflected light interference microscopy (RLIM) for the direct color photography of the surfaces of living normal and malignant cell cultures without the use of replicas, fixatives, or stains. The surface topography of living cells was found to follow underlying cellular structures such as nuceloli, nuclear membranes, and cytoplasmic organelles, making possible the study of their three-dimensional relationships in time. The technique makes possible the direct examination of cells grown on opaque as well as transparent surfaces. The successful in situ electron microprobe analysis of the elemental composition and distribution within single tissue culture cells was also reported.This paper deals with the parallel and combined use of scanning electron microscopy (SEM) and the two previous techniques in a study of living and fixed cancer cells. All three studies can be carried out consecutively on the same experimental specimens without disturbing the cells or their structural relationships to each other and the surface on which they are grown. KB carcinoma cells were grown on glass coverslips in closed Leighto tubes as previously described. The cultures were photographed alive by means of RLIM, then fixed with a fixative modified from Sabatini, et al (1963).

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