Research Progress on Sb Geochemistry and Sb Isotopes

Abstract

Antimony (Sb) has been widely used in products such as fire retardants, glass, rubber, paint, ceramics and semiconductors. It is found throughout igneous rocks but can be enriched in sedimentary rocks such as abysmal clays, shales and clastic rocks. Sb commonly occurs in magmatic sulfide deposits related to gabbroic rocks, sulfide deposits related to granitic rocks, clastic rocks and carbonate rocks hosted in stratified W-Sb-Hg deposits, and hydrothermal Pb-Zn deposits. The analytical method of high precision determination of Sb isotopes is now available. Samples are commonly digested with different types of acids, and Sb is separated and concentrated by cation exchange column combined with Thiol cotton fiber or both anion and cation exchange columns. Sb isotopes are determined by MC-ICP-MS coupled with hydride generation. The mass discrimination of equipment is commonly corrected by sample standard bracketing, using In and Sn internal standards. Different geological reservoirs have variable Sb isotope compositions (up to 18‱), with seawater of about 3.7‱, silicate rocks of 0.9‱ to 2.9‱, and sulfides (stibnite, sphalerite, pyrite, marcasite) of -1.9‱ to 16.9‱. Moreover, stibnites from different countries have different Sb isotope compositions. Glass from different places of production also shows different Sb isotope compositions. Sb isotopes will fractionate up to about 9‱ and 4‱ during oxide-reduction process (or sulfide precipitation) and inorganic absorption process, respectively. Therefore, Sb isotopes may serve as a geochemical tracer, which play an important role in indicating the source of ore-forming materials, portraying the ore-forming process and revealing the ore-forming mechanism. This isotope system can also be used to trace heavy metal pollution and can be used in archaeology.

Keywords

• sb isotopes
• geochemistry
• non-traditional stable isotopes
• isotope fractionation