Veins cutting the Brioverian sediments at Le Pulec, Jersey, were worked in the 1870s for silver and lead. Investigation of the mineralogy of both the sediments and cross-cutting veins has shown a complex mineralization history. Siltstones close to the contact with the North-West granite have been bleached, silicified, and dolomitized, and this has been accompanied by the introduction of pyrite, marcasite, and arsenopyrite. Later vein mineralization contains sphalerite and ferroan dolomite accompanied by lesser amounts of galena and chalcopyrite and minor quantities of argentian tetrahedrite, native antimony, bournonite, cubanite, plagionite, and stibnite. The mineral assemblage is unlike the other mineral occurrences of Jersey that have previously been described.