Investigation of ultrabasic rocks and beneficiation tailings of chromites from the Southern Kempirsaisk mine field

Abstract

The West-Kazakhstan Territorial Geological Commission is carrying out a detailed development study of the chromite deposits in the Southern Kempirsaisk mine field. A range of chromite ores with low Cr203 concentrations have been subjected to beneficiation. During chromite beneficiation, tailings are obtained consisting of magnesia--silicate material with a comparatively low impurity concentration. The accessory rocks of chromite strata are ultrabasic rocks related to serpentinized dunites of variable degree and their transition varieties.It was considered desirable to study the question of using these materials as raw material for producing magnesium silicate refractories which would expand the raw material base.This article gives the results for rocks and tailings from the Geophysical VII and Aleksandrovsk deposits of the Southern Kempirsaisk mining fields.Studies were made of two samples of ultrabasic rocks selected from the core of the drilling and three samples of tailings. The chromite beneficiation was done in the Uralmekhanobr Institute.In external appearance the ultrabasic rocks are uniform, gray in color with greenish shades, and they are dense in structure and finely crystalline.The open porosity of the rock is 0.1-0.2%, and the apparent density 2.51-2.56 g/cm 3.The tailings of chromite rock consist of a gray powder with greenish shades containing particles of not more than 0.2 mm in size. The specific surface is 0.93-1.63 m2/g.