Fingerprinting crystals

Claim 1

A process for fingerprinting a crystal selected from the group consisting of natural diamond, synthetic diamond and cubic boron nitride by implanting ions therein which impart to said crystal a predetermined structure which comprises providing said crystal with at least one external surface having a surface area of at least 0.1 square millimeter which is at least substantially smooth and without significant elevational differences, positioning said crystal in a chamber for ion-bombardment of at least said smooth surface thereof, providing said chamber with ionizing means for producing ions in beam form and means for accelerating the resulting implanting ions, evacuating said chamber, providing said chamber with a material to be ionized to produce implanting ions, sufficiently ionizing said material forming and accelerating a beam of the resulting implanting ions to selectively penetrate at least said smooth surface of said crystal to impart a predetermined structure thereto without significant deleterious damage to the appearance of said crystal, said chamber having been evacuated sufficiently to be free of at least significant contaminants, electrostatically charging the resulting characterized crystal so that at least said smooth surface of said crystal is electrostatically charged, applying a powder to said charged surface forming a powder pattern on said charged surface, said powder ranging in particle size from submicron to about 45 microns, said pattern being a delineation of the ion-implanted structure in said crystal.