Gold‐antimony mineralization at Loddiswell, Devon, UK

Native gold, in association with tetrahedrite, bournonite, bismuthian jamesonite, antimonian bismuth, chalcopyrite, sphalerite, gersdorffite, galena, covelline, yarrowite and acanthite occurs in a NW‐SE trending quartz carbonate vein which cuts folded Lower Devonian slates of the Meadfoot Group. The locality, 2.5 km north of the village of Loddiswell, lies in a belt of Devonian thrust and nappe terrain with a roughly E‐W trend. The host‐rocks are muddy turbiditic sediments interbedded with spilitic lavas, keratophyres and tuffs, together with intrusive dolerites (greenstones) which were deformed together during the Variscan orogeny. The deposit was worked briefly in the nineteenth century but little ore was raised and it is doubtful whether any gold was recovered. Analysis of samples collected in the present study revealed gold values of 5‐10 ppm and silver values of 1000‐2000 ppm. The relationship between gold‐antimony mineralization, the basic igneous rocks in the nappe sequence, and their intersection by a series of major NW‐SE fracture zones is discussed in the context of the regional metallogenic evolution of SW England. The mineralization is considered to be the result of fluid extraction during shear movements on the NW‐SE structures and shows features in common with mesothermal gold‐bearing sulphide veins in other Palaeozoic provinces.