Years and years ago I took two semesters of physics at Columbia and I was impressed by the real slate chalkboards in classrooms. Ever since than I wish to buy r

Years and years ago I took two semesters of physics at Columbia and I was impressed by the real slate chalkboards in classrooms. Ever since than I wish to buy real slate to use at home. Occasionally, I see them sold at ebay salvaged from schhols. But I wonder if there are manufacturers who sell new slate boards? Anyone know?