X-ray Emission Microanalysis of Rock-forming Minerals. VIII. Amphiboles

Abstract

Fifty-six amphiboles, ranging widely in composition, have been analyzed by X-ray emission techniques for Na, Mg, Al, Si, K, Ca, Ti, Mn, Fe as well as a number of minor elements. The electron probe data have been referred to non-amphibole standards, and have been converted to oxide weight concentrations by computer applied theoretical correction procedures. The analyses, performed in two different laboratories, are compared with independent wet chemical analyses of the same material. The agreement is in general within 5% of the amount present, though zoning is often responsible for discrepancies. Al is the only element which is systematically lower in probe analyses. Elements such as Cr, Ni, Zn, and Cl are often present in minor amounts.