Fluorite–barite–calcite–dolomite–iron–manganese mineralisation at Craigmuschat quarry, Gourock; a historical review

Abstract

Synopsis Two types of mineralisation are hosted by the Craigmuschat trachyte sill. The first occurs as geodes variably composed of fluorite, quartz, chalcedony, hematite, goethite, wad, romanechite, calcite, dolomite, baryte, gypsum, tourmaline, ankerite and prehnite. The second type, composed dominantly of hematite with lesser baryte, quartz, calcite and manganese oxides, is represented by coatings along joint planes and discrete veinlets. The proposed infilling of this quarry SSSI, with subsequent loss of much of the exposed mineralisation, initiated this review. Material from the quarry available in museums for examination is listed as an appendix.