Black Furnace Cement is premixed and ready to use making it one of the easiest cements to apply. Use this smooth consistency cement to bond and seal metal to metal or metal to masonry joints less than 1/8". Fix a crack or seal the collar to the top of your wood stove or seal between your firebricks and prefabricated fireplace. Use this cement anywhere else you need a high temperature adhesive for furnaces, firebrick repair, filling gaps, sealing joints or gluing ceramic logs.