A diamond tool 1 comprising a tool tip 5 of boron-containing single-crystal diamond.

A generally round setting for a diamond, which simulates the appearance of a larger diamond, comprises an annulus and three prongs. The annulus has an upper surface stamped with from nine to twenty-one equally spaced apart, radially extending cuts providing reflecting surfaces, each of the cuts being wedge shaped in plan and V-shaped in cross section. The three equally spaced apart prongs are upstanding from the annulus upper surface for receiving and holding the diamond.

A precious stone setting, preferably for invisibly mounted diamonds, is obtained by forming cutouts on opposed facets of square-shaped diamonds with a saw which is held at a downwardly pointed angle relative to the tables of the diamonds. Forming the cutouts in this manner produces in the pavilions of the diamonds, below their girdles, upwardly pointed biting edges, and clearances above these edges. The diamonds thus prepared are set in a setting comprising walls which extend parallel to one ano...

There is provided a diamond crystal in which the (111) oriented plane is of the diamond crystal synthesized on a substrate by a chemical vapor deposition method parallel to a substrate surface, and the area of the (111) oriented plane parallel to the substrate surface is 1/24 or less an area of the crystal on the substrate.

A method of producing diamond crystal growth on a seed crystal is provided. The method includes the steps of providing a seed crystal containing at least one twin plane and re-entrant growth surfaces associated therewith and applying high temperature/high pressure synthesis conditions to the seed crystal to cause diamond growth to occur preferentially on the re-entrant surfaces. The diamond growth on the seed crystal results in a diamond crystal being produced which has an aspect ratio greater t...

The present invention is a diamond electrode with high efficiency, a small overvoltage, and a long lifetime, which is reusable, and which can measure the temperature of the electrode. The diamond electrode is at least partially composed of a semiconducting diamond film, whose surface is chemically modified. Another embodiment of the present invention carbon is used as a bare electrode material, diamond crystals are fixed to the bare electrode material, the surface of the undoped diamond crystals...

A method of doping diamond with relatively large atoms such as aluminium, phosphorus, arsenic and antimony is provided. The method involves implanting the dopant atoms at a low temperature to create a damaged region of point defects in the form of vacancies and interstitial dopant atoms within the crystal lattice of the diamond, and annealing the diamond to reduce the lattice damage and cause dopant interstitial atoms to diffuse into lattice positions. The implantation dose will be low and such ...

A diamond tool, e.g., cutting tool, dresser, wire drawing die, etc., having excellent wear resistance, heat resistance and oxidation resistance and with an improved tool life is provided, which is mainly composed of a synthetic diamond single crystal containing boron or boron and nitrogen.

A diamond thermistor having a pair of diamond contact regions having a low resistance formed on a temperature sensing diamond substrate. The formation of the diamond contact regions is carried out by depositing a diamond film using a carbon compound gas and a dopant gas and etching the diamond film to leave the contact regions by an etchant including fluorine or oxygen.

A diamond without plate is described, in which the facets of the upper part are more slanted toward the girdle level than the facets of the lower part. To create a diamond that, with the least possible quantity of material, gives one an impression of hardness and clarity when looking down on it, the angle between one of the equally large upper part facets and the preferably polygonal girdle level as well as the angle between one of the equally large lower part facets and the girdle level is chos...