Abstract: A method for positioning a diamond stone in an indented shank is described. A wetting agent put in contact with a diamond draws it upwardly into the indentation in the shank. A brazing material is added to the wetting agent to be drawn into the interface between the diamond and the shank indentation. After drying the wetting agent from the assembly, a laser beam heating the shank effects a strong, acid resistant braze of the shank and diamond. A novel brazing material in weight percent of 71% silver, 28% copper, 0.75% nickel, with 0.25 to 0.35% in the aggregate of any one or more of ruthenium, rhodium or iridium provides a strong bond with significant acid resistance.

Abstract: A technique for aligning a surface of a workpiece with respect to a positioning ring attached to a holder supporting the workpiece comprises mounting the holder on an alignment platform adjacent a positioning block attached thereto for holding the positioning ring in a predetermined position. The holder is adapted to rotate the workpiece, with respect to the positioning ring, about a first axis, and the alignment platform is supported by a table. The surface of the workpiece is exposed to an incident light beam, whereby the incident beam is reflected from the surface, as a reflected beam, onto a screen along a path of alignment marks disposed thereon. The surface is then rotated about the first axis to change the location where the reflected beam strikes the screen, whereby the surface is properly aligned with respect to the positioning ring when the reflected beam strikes a particular location on the screen.

Abstract: An apparatus for sorting stones contained within a supply reservoir by viewing the stones individually through a microscope includes a pick-up tube having a first opening disposed at one end thereof, the first opening adapted to form a substantially airtight seal with one of the stones. A vacuum source is connected to a second opening disposed at the other end of the pick-up tube, the second opening being in communication with the first opening. The apparatus further includes support apparatus connected to the other end of the pick-up tube for moving the one end of the tube between a first position disposed at a transfer location whereat the one end is exposed to the stones within the supply reservoir, and a second position outside the reservoir whereat the one end is positioned exactly within the field of view of an objective of the microscope such that a stone held adjacent the first opening is disposed precisely at the focal length of the microscope objective.

Abstract: A lapping machine includes a circular drive plate mounted on the end of a driven shaft and a circular lapping plate mounted on the drive plate. A pair of leveling levers are mounted between the drive plate and the lapping plate with each lever being in a groove in the drive plate. Each lever has a pivot point adjacent one end which is pivotedly seated on the drive plate and projects from the groove in the drive plate so that the lapping plate engages the lever. An adjustment screw is at the other end of each lever for adjustably pivoting the lever and thereby tilts the lapping plate with respect to the drive plate. Either the lapping plate or the drive plate has holes therethrough to permit access to the adjustment screws. A drive pin projects from the drive plate and fits in a groove in the bottom of the lapping plate to drive the lapping plate with the drive plate.

Abstract: A work holder includes an elongated, hollow, cylindrical handle and a head secured within one end of the handle. A fixed jaw is secured to the head and projects longitudinally from the end of the handle. The fixed jaw has a pointed tip on its free end. A movable jaw is over the fixed jaw and is pivotally seated on an annular flange on the head. The movable jaw has a pointed tip which contacts the tip of the fixed jaw. A spring extends around the two jaws. The spring normally holds the tips together but allows pivoting of the movable jaw to separate the tips and thereby allow insertion or removal of a workpiece.