An intermetallic bonded diamond composite composition and methods of processing such a composition are provided by the present invention. The intermetallic bonded diamond composite composition preferably comprises a nickel aluminide (Ni3Al) binder and diamond particles dispersed within the nickel aluminide (Ni3Al) binder. Additionally, the composite composition has a processing temperature of at least about 1,200° C. and is processed such that the diamond particles remain intact and are not converted to graphite or vaporized by the high-temperature process. Methods of forming the composite composition are also provided that generally comprise the steps of milling, pressing, and sintering the high-temperature intermetallic binder and diamond particles.