Abstract: There is disclosed an apparatus and method for sorting gemstones from a batch of gemstones. The apparatus comprises one or more measurement locations, each comprising at least one measurement device configured to measure one or more properties of a gemstone. A continuously moveable surface supports the gemstones thereon and transports the gemstones to the one or more measurement locations. A separation device separates the gemstones from one another as they are transported on the moveable surface to the one or more measurement locations. A location trigger at a sensor location comprises a sensor for identifying when the gemstone passes through the sensor location.

Abstract: There is disclosed an apparatus and method for sorting gemstones from a batch of gemstones. The apparatus comprises one or more measurement locations, each comprising at least one measurement device configured to measure one or more properties of a gemstone. A continuously moveable surface supports the gemstones thereon and transports the gemstones to the one or more measurement locations. A separation device separates the gemstones from one another as they are transported on the moveable surface to the one or more measurement locations. A location trigger at a sensor location comprises a sensor for identifying when the gemstone passes through the sensor location.

Abstract: Apparatus and corresponding methods for measuring a plurality of parameters of a cut gemstone while it is positioned at a single measurement location. Apparatus comprise a plurality of light sources, each configured to emit light at a different one of a plurality of emission wavelengths or ranges of wavelengths such that the emitted light illuminates at least part of the measurement location. Apparatus further comprise a sensor assembly configured to sense light at a plurality of sensing wavelengths or ranges of wavelengths for measuring the plurality of parameters. The sensed light is received at the sensor assembly from the measurement location as a result of illumination of a cut gemstone located at the measurement location.

Abstract: 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 (38) extending generally along the direction of the path; and generating relative oscillatory movement (14) between the pair of walls (38) and the travelling path (in a direction generally transverse to the direction of the path), so that the pair of walls (38) 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.

Abstract: A single crystal CVD synthetic diamond layer comprising a non-parallel dislocation array, wherein the non-parallel dislocation array comprises a plurality of dislocations forming an array of inter-crossing dislocations, as viewed in an X-ray topographic cross-sectional view or under luminescent conditions.

Abstract: Apparatus and corresponding methods for measuring a plurality of parameters of a cut gemstone while it is positioned at a single measurement location. Apparatus comprise a plurality of light sources, each configured to emit light at a different one of a plurality of emission wavelengths or ranges of wavelengths such that the emitted light illuminates at least part of the measurement location. Apparatus further comprise a sensor assembly configured to sense light at a plurality of sensing wavelengths or ranges of wavelengths for measuring the plurality of parameters. The sensed light is received at the sensor assembly from the measurement location as a result of illumination of a cut gemstone located at the measurement location.

Abstract: The invention provides a method of automating the classification of a diamond gemstone. An infra-red absorption spectrum of the gemstone is provided. Features corresponding to absorption by water and intrinsic absorption by a diamond lattice are subtracted from the absorption spectrum. The spectrum is analysed to identify predetermined absorption features corresponding to lattice defects in the diamond. The gemstone is classified according to the intensities of the predetermined absorption features. The results of the classification are saved in a database.

Abstract: 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 (38) extending generally along the direction of the path; and generating relative oscillatory movement (14) between the pair of walls (38) and the travelling path (in a direction generally transverse to the direction of the path), so that the pair of walls (38) 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.