Metamorphic Vanadian–Chromian Spinel (Sludyanka Complex, South Baikal Area). Ferroan Spinel

Abstract

Abstract —V–Cr-spinel of wide composition range is present as a rock-forming or accessory mineral in parametamorphic rocks of the Sludyanka Complex (South Baikal area, Siberia, Russia). The spinel can be subdivided into two large groups: magnesian spinel and ferroan spinel. In this paper we describe ferroan spinel. It is subdivided into three groups: (1) Zn–V-bearing and vanadian (up to 5 wt.% ZnO and up to 19.5 wt.% V2O3); (2) V-bearing zinc spinel and vanadian zincochromite (up to 6 wt.% V2O3 and 5.0–20.3 wt.% ZnO); and (3) Zn–V spinel and zincochromite (>6 wt.% V2O3 and 5.0–22.2 wt.% ZnO). A separate small group of ferroan spinel is represented by ternary chromite–coulsonite–magnetite solid solution. In addition to the Slyudyanka spinel, we present a summary of metamorphogenic chromium and vanadium spinel from other deposits. The behavior of Cr, V, and Zn in metamorphic and magmatic spinel is discussed.