A multi-functional precious stone testing apparatus includes a microcontroller, a measuring unit for measuring properties of the testing object, and a functional unit. The measuring unit is arranged to measure one of a combination of ultraviolet and infrared distributions of the testing object and a combination of thermal and electrical conductivities of the testing object. The microcontroller analyzes a result from the measuring unit to generate a test result of the testing object, wherein the microcontroller includes a communication unit for connecting with an electronic device to transmit the test result thereto. The functional unit includes a voice indicator that generates a voice indication signal of the test result.

The fingerprint comprises a three-dimensional map of internal imperfections present in a crystal within the gemstone (5), and may also comprise further information about the gemstone (5). The method comprises scanning the gemstone in an imaging apparatus by recording diffraction and/or extinction images according to a scanning strategy, and generating a fingerprint from the recorded diffraction and/or extinction images. The imaging apparatus comprises a sample holder (4), a sample stage (3), a detector (6), an x-ray source (1), wherein the sample holder (4) is movable relative to the x-ray source (1) and the detector (6). The fingerprint is used for the identification of gemstones, and/or for tracking and/or processing of gemstones in a supply chain.

A system for the automatic grading of a cut/polished gemstone (SUT) includes an enclosure with a stage for mounting the cut/polished SUT. The enclosure further includes one or more sources of broadband visible (BBV) light, the sources of BBV light being controllable by a programmable controller; an image sensor for capturing a plurality of images of a mounted SUT, and one or more sources of UV light mounted within the enclosure. The controller captures images of the mounted SUT from one or more selected angles relative to the sensor elevation axis and relative to the position of the SUT on the stage rotation axis; an image capturing module is configured for processing the one or more images; and, a light grade calculation module is configured for grading the cut/polished SUT using light indicative parameters from at least a part of the one or more images captured.

A method for grading a precious gem. The method may include generating, by a signature generator, a signature of the precious gem; searching, out of multiple concept structures, for a matching concept structures that comprises at least one reference signature that matches the signature of the precious gem; wherein each concept structure comprises precious gem signatures of the same grade; wherein at least two concept structures differ from each other by grade; wherein each concept structure is generated by applying an unsupervised learning process and associating a grade with the cluster; and determining the grade of the precious gem based on a grade associated with a matching concept structure.

Provided herein is an apparatus for assessing a fluorescence characteristic of a gemstone. The apparatus comprises an optically opaque platform for supporting a gemstone to be assessed, one or more light source to provide uniform UV and non-UV illumination, an image capturing component, and a telecentric lens positioned to provide fluorescent images of the illuminated gemstone to the image capturing component. Also provided are methods of fluorescence analysis based on images collected using such an apparatus.

The present invention describes a device and a method for grading diamonds using electromagnetic fields with a radiofrequency or terahertz frequency. The method for grading diamonds comprises placing the diamond (4) into a grading device, applying an electromagnetic field with a frequency range of up to 30 THz to the diamond, recording a modulated signal received from the diamond in a form of S-parameters as a function of frequency or any other parameter that can be deduced by applying said electromagnetic field, processing the recorded signal in the processing unit to obtain data containing information about either an amplitude, or phase, or both of the recorded S-parameters as a function of frequency or said any other parameter, performing calculations relating to the obtained data, and running a computer algorithm correlating the calculated data to either nitrogen concentration, boron concentration or plastic deformation in diamonds, thereby allowing grading of the diamond. The device comprises the following components, RF generator (1), transmitting antenna (2), waveguide (3), receiving antenna (5), amplitude and frequency detector (6) and computing unit (7).

The application provides a diamond testing device. The testing device includes a casing, a movable specimen holder, an illumination unit, a light sensor unit, and a computing processor. In a closed position, the casing encloses the specimen holder, the illumination unit, and the light sensor unit.

A system for the automatic grading of a cut/polished gemstone (SUT) includes an enclosure with a stage for mounting the cut/polished SUT. The enclosure further includes one or more sources of broadband visible (BBV) light, the sources of BBV light being controllable by a programmable controller; an image sensor for capturing a plurality of images of a mounted SUT, and one or more sources of UV light mounted within the enclosure. The controller captures images of the mounted SUT from one or more selected angles relative to the sensor elevation axis and relative to the position of the SUT on the stage rotation axis; an image capturing module is configured for processing the one or more images; and, a light grade calculation module is configured for grading the cut/polished SUT using light indicative parameters from at least a part of the one or more images captured.

A method for identifying the presence of partly liberated diamonds in a material stream. The method including illuminating a material with a multi-wavelength beam including at least one monochromatic SWIR laser beam, and at least one IR scatter-/anti-scatter laser beam. A sorting process including ejecting objects including material classified as diamond from a transportation direction of the material stream.

A method and system for determining a location of artefacts and/or inclusions in a gemstone, mineral or sample thereof, the method comprising the steps of: surface mapping a gemstone, mineral or sample thereof to determine surface geometry associated with at least a portion of a surface of the gemstone, mineral or sample thereof; sub-surface mapping the gemstone, mineral or sample thereof using an optical beam that is directed at the surface along an optical beam path, wherein the optical beam is generated by an optical source using an optical tomography process; determining a surface normal at the surface at an intersection point between the optical beam path and the determined surface geometry; determining relative positioning between the surface normal and the optical beam path; and determining the location of artefacts and/or inclusions in the gemstone, mineral or sample thereof based on the sub-surface mapping step and the determined relative positioning.