Method of making slabs of building material which can be used in place of slabs of compact marble are prepared by lining at least one surface of a mold with bonding material, introducing into the mold pieces of solid material to form an aggregate of individual pieces of said solid material with interstices therebetween, filling these interstices with bonding material which chemically bonds to the bonding material utilized for lining, allowing the bonding material to cure and harden to form a solid block of lined material, removing the solid block of lined material from the mold and slicing said block to desired size.