Our local masonry supply carries only Whitacre-Greer firebrick... A product that I've been somewhat less than satisfied with in recent years. Our only alternative would be to special order Alsey firebrick, which has always seemed to be more of a pain than it's worth, but I'm not so sure any more.... My latest beef; the firebrick we're getting has always had a 'dusting' of brick dust between the layers on the skid. Lately though, they are using RED brick dust between the layers of BUFF firebrick. This results in dicoloration of the brick... Not sure if thus is due to the red dust being 'ground' in to the face of the brick during transport, or perhaps due to getting wet during improper storage... Or what...? In any event, there are too many discolored brick to simply avoid using those. I'm going to try washing a few today, and am wondering about an appropriate cleaner... Any thoughts on an appropriate product?