Disclosed herein is an improved method for joining diamond to metal using a gold-tantalum or gold-niobium solder. The method utilizes powdered material, and a clamp to keep the diamond in place during the soldering step. The article produces has higher mechanical stability than articles produced by known procedures.

The invention applies to locking means designed to prevent the theft of diamond needles from phonograph tone arms. In the sale of phonograph and stereo equipment a diamond needle is used on the tone arm in coaction with a record. The diamond needles are quite valuable and where the equipment is on display to purchasers the needles are frequently stolen. The invention keeps the needle locked against theft and allows the salesman to quickly and easily remove the locking means and demonstrate the o...

An improved adjustable diamond faceting platform is described of the type adapted to be mounted on a tong and suitable for supporting a dop. The adjustable diamond faceting platform of the present invention includes a worm gear mounted on the platform. The worm gear has an axis of rotation and includes means for connecting a dop to the worm gear for common rotation about the axis. A worm is rotatably mounted on the platform proximate to the worm gear for meshingly engaging the latter and for rot...

Feed frame assembly for supporting and feeding drill head which rotates drill rod about axis. Assembly includes spaced front and rear end members, laterally spaced longitudinal members and first and second hydraulic feed cylinders. Longitudinal members and feed cylinders extend between end members and are parallel to rod axis. Piston rods of feed cylinders have double-acting pistons cooperating with cylinder bodies to feed head along the piston rods. Stabilizer cylinders in longitudinal members ...

This novel invention consists of a diamond grinding wheel having its cutting surface formed at a predetermined angle in relation to the spindle supporting and rotating the aforesaid wheel on a grinding machine. The grinding wheel is bonded to a ring that is secured by a plurality of headless screws to a circular mounting flange that is fastened to the aforesaid spindle of the grinder.

A diamond bonding process wherein a metallic workpiece is pre-etched and thereafter diamond is uniformly and densely bonded to the surface of said metallic workpiece in a nickel matrix. A novel second plating of nickel metal more securely bonds the diamonds to the workpiece.

Diamond crystals of controlled impurity content and/or impurity distribution and reaction vessel configurations for the production thereof are described. Combinations of "dopant", "getter" and "compensator" materials are employed to produce gem stones of unusual color patterns, or zoned coloration, using specific reaction vessel configurations.

A diamond hone for re-working and correcting lead and involute profile of hardened gears which is characterized by a monolayer of diamond abrasive bonded to a gear hone which is provided with a unique geometry wherein the tip and pitch diameter portions are specifically formed to obtain a predetermined deviation from the true involute form conventionally employed. This new diamond hone and unique geometry imparts the desirable final geometry in the re-worked gear.

A drill for use in drilling precious and semi-precious stones consisting of a body adapted to be rotated on its axis, said body having longitudinal cutter elements separated by longitudinal flutes, the surfaces of the body of said drill being covered by an abrasive layer consisting of a ductile metal, such as nickel, containing a multiplicity of abrasive particles.

The invention provides elongate synthetic RD diamond particles, each particle having a long axis and a short transverse axis, the ratio of the long axis to the short axis being at least 3 to 1. Each particle generally has a rib bed structure down its long axis, the ribs of the structure being traces of {111} crystallographic planes and the long axis providing a backbone for the structure and being in the direction <100> crystallographic direction. The invention further provides a resin bon...