NPRNTitleType Of SiteArchivesImagesNPRN416220TitleSmithy Attached to Floor 6 Mill, Diffwys Slate QuarryType Of SiteMETAL WORKSArchives2Images2NPRN415671TitleMill, Floor 6, Diffwys Slate QuarryType Of SiteSLATE PROCESSING WORKSArchives29Images27