Method of forming a composite panel

A method of forming a composite panel with a facade comprising a planar arrangement of thin facers on a body of structural backing material;

• said method comprising the steps of providing a substantially flat casting bed, providing a plurality of facers each having a substantially rectangular configuration with recesses along at least one rear end wall corner and along at least one rear side wall corner, arranging the plurality of individual facers in abutting relationship atop the casting bed and in a selected geometrical pattern in a face down planar configuration so that recesses on the facers open rearwardly and cooperatively define narrow elongated channels at joints between contiguous facers, depositing a sealant in the channels between facers to prevent the structural backing material from penetrating the joints between during casting and defacing the front surfaces thereof, casting structural material behind the facers to conform and adher to the rear surfaces thereof and form a composite panel.