Abstract: A continuous casting process and slab plate mold for casting an endless solidified steel shell enclosing a liquid core which is formed of spaced parallel longitudinal wall plates having held therebetween spaced inwardly tapered transverse wall plates provided with specially contoured inner surfaces comprising flat sections extending inwardly from each longitudinal edge disposed perpendicular to the longitudinal wall plates and having a length about equal to the thickness of the wide walls of the casting shell at the lower end of the mold with the inner ends of said flat sections being connected by a convex section whose curvature is such that the convex section is maintained in supporting contact with said casting as the casting is moved downwardly through said mold; whereby the pressure of the casting shell on the transverse wall plates is evenly distributed so that uneven wear is avoided and the working life of the transverse wall plate substantially extended.