De Beers UK Ltd

De Beers Centenary Ag

Gersan Establishment

Graham Ralph Powell

James Gordon Charters Smith

Michael Peter Gaukroger

Trevor John Poulter

James Gordon Smith

Nicholas Matthew Davies

Siobhan D'Gama

Qi He Hong

Keith Barry Guy

Maxwell Ralph Willis

James G C Smith

Andrew Portsmouth

Siobhan D'gama

Trevor Poulter

A method and apparatus for orientating discrete objects, such as gemstones, is described. The method comprises providing the objects on a travelling path; providing a pair of opposed walls () extending generally along the direction of the path; and generating relative oscillatory movement () between the pair of walls () and the travelling path (in a direction generally transverse to the direction of the path), so that the pair of walls () imparts lateral force to the objects to thereby urge them into their most stable orientation as they progress along the path. A device for checking the orientation of the discrete objects is also described.

Automatic gemstone orientation

A method and apparatus for generating a 3D model of and/or detecting inclusions in a polished gemstone such as diamond is described. The gemstone () is rotated in a series of discrete increments. At each rotational position of the gemstone, the gemstone () is illuminated with collimated light () and a silhouette image recorded. At each rotational position, the gemstone () is also (before further rotation) illuminated with diffuse light (), and a diffuse image recorded. The images are analyzed to obtain a 3D model of the surface of the gemstone. Features may then be identified in the diffuse images and tracked between subsequent diffuse images. The tracked features may be located relative to the 3D model of the gemstone, taking into account reflection and refraction of light rays by the gemstone. Some or all of the located features may then be identified as inclusions.

Inclusion detection in polished gemstones

An apparatus and method for aligning a gemstone such as diamond () with a predetermined vertical axis () is described. The apparatus includes an upwardly extending nozzle () aligned with the vertical axis () and sized to allow the gemstone () to settle into it under the action of gravity so that the article is supported by the aperture. A fluid supply system supplies fluid to the nozzle () under sufficient pressure to support the article within or above the aperture. A fluid pressure control system controls the pressure of fluid supplied to the nozzle (), so that it can be reduced gradually.

Gemstone alignment

An invisible information mark is provided on a facet of a diamond gemstone by applying a plasma resist to the exposed surface of the gemstone, applying an electrically conducting layer of metal to the region where the information mark is to be formed, ablating a selected zone of the metal and resist layers by ultraviolet laser thus forming a mask on the surface of the facet, electrically connecting the metal layer and plasma etching the facet through the mask, thus forming a mark of appropriate depth on the surface of the gemstone.

Marking diamond

Growing community of inventors

Berkshire, United Kingdom

Graham Ralph Powell