An SEM-EDX and Raman spectroscopic study of the fibrous arsenate mineral liskeardite and in comparison with other arsenates kaňkite, scorodite and yvonite.

The mineral liskeardite, an arsenate mineral with major cations of iron and aluminium, has been studied by a combination of scanning electron microscopy with energy dispersive spectroscopy and Raman spectroscopy. The mineral shows a fibrous nature. Semi-quantitative chemical analysis shows an Al and Fe arsenate phase with minor amounts of K, Cu, S and Si.

SEM, EDX and vibrational spectroscopy of the phosphate mineral vauxite from Llallagua, Bolívia.

We have undertaken a vibrational spectroscopic study of vauxite from Llallagua, Bolívia. This source is important source for rare and unusual secondary phosphate minerals and is the type locality for a number of rare phosphates such as vauxite, sigloite, metavauxite and for jeanbandyite. The chemical formula was determined as (Fe0.

A vibrational spectroscopic study of the phosphate mineral vantasselite Al4(PO4)3(OH)3·9H2O.

We have studied the phosphate mineral vantasselite Al₄(PO₄)₃(OH)₃·9H₂O using a combination of SEM with EDX and Raman and infrared spectroscopy. Qualitative chemical analysis shows Al, Fe and P. Raman bands at 1013 and 1027 cm(-1) are assigned to the PO₄(3-)ν₁ symmetric stretching mode.

A vibrational spectroscopic study of the anhydrous phosphate mineral sidorenkite Na3Mn(PO4)(CO3).

Sidorenkite is a very rare low-temperature hydrothermal mineral, formed very late in the crystallization of hyperagpaitic pegmatites in a differentiated alkalic massif (Mt. Alluaiv, Kola Peninsula, Russia). Sidorenkite Na3Mn(PO4)(CO3) is a phosphate-carbonate of sodium and manganese.

Structural characterization and vibrational spectroscopy of the arsenate mineral wendwilsonite.

In this paper, we have investigated on the natural wendwilsonite mineral with the formulae Ca2(Mg,Co)(AsO4)2⋅2(H2O). Raman spectroscopy complimented with infrared spectroscopy has been used to determine the molecular structure of the wendwilsonite arsenate mineral. A comparison is made with the roselite mineral group with formula Ca2B(AsO4)2⋅2H2O (where B may be Co, Fe(2+), Mg, Mn, Ni, Zn).

Vibrational spectroscopy of the phosphate mineral lazulite--(Mg, Fe)Al2(PO4)2·(OH)2 found in the Minas Gerais, Brazil.

This research was done on lazulite samples from the Gentil mine, a lithium bearing pegmatite located in the municipality of Mendes Pimentel, Minas Gerais, Brazil. Chemical analysis was carried out by electron microprobe analysis and indicated a magnesium rich phase with partial substitution of iron. Traces of Ca and Mn, (which partially replaced Mg) were found.

Infrared and Raman spectroscopic characterization of the phosphate mineral fairfieldite--Ca2(Mn2+,Fe2+)2(PO4)2·2(H2O).

Raman spectroscopy complimented with infrared spectroscopy has been used to determine the molecular structure of the phosphate mineral fairfieldite. The Raman phosphate (PO4)(3-) stretching region shows strong differences between the fairfieldite phosphate minerals which is attributed to the cation substitution for calcium in the structure. In the infrared spectra complexity exists with multiple (PO4)2- antisymmetric stretching vibrations observed, indicating a reduction of the tetrahedral symmetry.