Back in 2011, before the police got touchy about people wandering around the old General Shale property (there had been a LOT of vandalism), I would walk over there with my camera and take pix of stuff lying about.  This is apparently a display showing the different colors that General Shale could product on exposed brick surfaces.  These are all stringers.  No headers are shown, so I don’t know if they were also treated or if these were just for decorator areas.