Since the days of the Roman empire, alum was used as a mordant or fixative that allowed textiles to be colored using vegetable dyes. Initially imported from Italy where there was a Papal monopoly on the industry, the supply to Great Britain was cut off during the Reformation in England. In response to this need, during the 16th century, Thomas Challoner found that fossils in shale along the Yorkshire coast were the same as those found in alum producing areas of Italy and Europe and, as a result, an alum…
Read MoreThe strange story of why human urine was transported to quarries in North East Yorkshire
