After Imperial influence waned, the mines were held in pledge by the council of the Imperial city of Goslar, who officially purchased the entitlement to the rights and royalties from mining (Bergregal) in 1359. A mining accident is documented in 1376, when more than 100 miners were buried and killed. The main ores mined at Rammelsberg were lead-zinc ore, copper ore, sulphur ore, mixed ore (Melierterz), brown spar (Braunerz), barite ore (Grauerz), banding ore (Banderz) and kniest along with the important minerals of galena, chalcopyrite, sphalerite, baryte and vitriols. The chief metals extracted from these ores included silver, lead, copper and zinc, on which the wealth of Goslar was based.