Chemical laboratory of IGEM RAS executes all types of chemical quantitative analyses of mineral objects using a combination of modern physicochemical and classical methods of analyses (atomic-absorptional one, emission spectrophotometry, ICP-MS spectroscopy, ionometry with ion-selective electrodes, spectrophotometry based on reactions with new analytical reagents etc.
Correctness of analysis is controlled by parallel analysis of standard samples or using an addition method, and, in the case of complete silicate analysis, - by the total concentration of all components that have to be between 99.5 - 100.5 %. Relative error of determination for spectrophotometric methods comprises 1 - 2 %, and relative standard deviation Sp = 2-3 %.
Correctness of analysis is controlled by parallel analysis of standard samples or using an addition method, and, in the case of complete silicate analysis, - by the total concentration of all components that have to be between 99.5 - 100.5 %. Relative error of determination for spectrophotometric methods comprises 1 - 2 %, and relative standard deviation Sp = 2-3 %.
COMPLETE CHEMICAL ANALYSIS OF ROCKS
1. Classical (gravimetric) analysis
Conventional determinable major components : SiO2, TiO2, Al2O3, Fe2O3, FeO, MnO, CaO, MgO, K2O, Na2O, H2O-, H2O+.
Additional determinable components: C, CO2, S, Cl, P, Li, Rb, Sr, Ba.
Microelements: Be, Cr, Y, Cu, Ni, Co, Zn, Pb, Cd, TR (should be specified).
Necessary weight of the sample: 3-5 g (ground to 200-300 mesh).
COMPLETE ANALYSIS OF SULFIDE ORES AND MINERALS
Determinations , with the use of both classical and physicochemical methods, are performed for major and accessory elements: Ag, Au, Cu, Ni, Co, Mn, Fe, Zn, Pb, Cd, Bi, Hg, As, Sb, Sn, S, Se, Si, Ca, Mg.
Necessary weight of the sample: 2 -10 g (for ores) and 1 -2 g (for minerals).
COMPLETE CHEMICAL ANALYSIS OF MINERALS
1. Macroanalysis (weight of the sample should be 1.5 - 2 g, no grinding)
Minerals being analysed: silicates, aluminosilicates (mica, chlorite, feldspar, garnet etc.), borates (tourmaline etc.), arsenides, selenides etc., wolframites, molybdates, bismutides etc., titanium niobates, zirconium- and titanium silicates, rare earth' minerals.
2. Microanalysis (weight of the sample should be 200 mg, no grinding)
Minerals being analysed: silicates and titanomagnetites for major and accessory elements.
Beside the complete analysis, determinations of additional special elements are performed from separate samples: Ca, Mg, Si, Ti, Al, Fe2+, Fe3+, Mn, Cr, Ni, Cl, CO2, F, H2O etc.
COMPLETE CHEMICAL ANALYSIS OF WATERS
Natural and industrial (sewage) waters are analysed for major components:
Ca, Mg, Na, K, SO2 -, Cl, HCO3-, H2SiO3, Fe3+, Fetot, pH, oxidation ability, free O2 and H2S. Additional determinations, with a preconcentration of material using organic chelate adsorbents, can be made for microelements with the concentration level around n.10-3 - n.10-5 %.
DETERMINATION OF SEPARATE MICROELEMENTS
in minerals, rocks, natural and industrial waters at the level of n - n.10-7%:
n - n.10-2% - Ca, Mg, NH4+, C, CO2, Cl, Fe2+, Fe3+, F, P, SO42-.
n - n.10-3% - K, Na, Sr, Ba, Fe, Mo, Sb, Al, As, Cr, Y, TR, F.
n - n.10-4% - Cu, Ni, Co, Cd, Pb, Mn, Sn, Mo, Sc, Zr (for lower limit, with the preconcentration by absorbents).
n.10-4 - n.10-5% - Li, Rb, Cs, Te, Se (with the preconcentration).
n.10-5 - n.10-7% - Au, Ag (with the preconcentration by absorbents).
Necessary weight if the sample is dependent on the number of elements to be analysed, volume of the water - 0.1 - 0.5 l.
Determinations are performed with the atomic-absorptional spectrophotometry, ionometry and with the use of ICP-MS machine VG Plasma Quad.
Head of Analytical Laboratory - Dr. G.O.PiloyanE-mail: piloyan@igem.msk.suFax: (7-095) 230-2179
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