Was redoing the bottom of my forge floor. i hadnt planned on doing any forge welding in it and didnt do the floor right. Well the flux ate a hole in the floor so i decided to pull the floor out and redo it. not knowing or realizing what i was truly dealing with i went in bare handed and with a screwdriver and hammer chisled out the floor. Well let me tell you that stuff is super sharp, on the order of nice clean glass break and will cut you good i know and so does the end of my finger. So let my tore up finger be a leason to all hardend flux on forge floor can be very sharp.