Structural and Mineralogical Imperfections of Some High Grade Quartz Ores Diagnose Their Chemical Reactivity

ABSTRACT

The grade of a quartz ore is not a measure of its chemical reactivity. A high grade quartz sample (B) showed low reactivity in sodium silicate production. Structural imperfection usually occurs due to lattice defects in the quartz tetrahedron as a result of several substitutions that happen during mineralization. The random distortion of the quartz tetrahedron that could be affected by various mechanical and thermal stresses is accompanied by similar distortion in the crystallinity index which could be the reason for better chemical reactivity. The imperfect crystallinity of quartz sample (A) accompanied by highly shear petrography with micro-veinlets and fissures in its matrix has a direct impact on its fineness as revealed by its low grindability index (17.9 kwh/t) and highly surface area (13.07 m²/g) measurements. Both properties enhance chemical reactivity of quartz sample (A). Both structural and physical imperfection of quartz affect its chemical reactivity not only its grade.

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