Yellow Mn-rich tourmaline from the Canary mining area, zambia

Abstract

The most important source of yellow gem elbaite is the Canary mining area in the Lundazi District of eastern Zambia. The tourmaline has been mined since 1983 from both pegmatite and eluvial/alluvial deposits, in colors typically ranging from yellow-green to yellow to orange and brown; much of the orange-to-brown material is heated to attain a "golden" or "canary" yellow color. The tourmaline is Mn-rich (up to 9.18 wt.% MnO documented in the literature) and contains traces of Ti and little or no Fe. The distinctive composition of this tourmaline is probably the result of the crystallization of abundant schorl from an unusual B-rich, Li-poor pegmatite magma, which depleted Fe while conserving Mn until the late-stage crystallization of gem pockets. © 2007 Gemological Institute of America.