Abstract: 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.

Abstract: Systems and methods for determining properties of gemstones based, inter alia, on fluorescence properties of the gemstones, are presented. In one aspect, properties of at least one gemstone can be determined. In another aspect, a relationship between at least two gemstones can be determined. In one example, a first and a second gemstones are illuminated with illuminating light of at least one fluorescence-exciting wavelength range; corresponding at least one first fluorescence-emission light and at least one second fluorescence-emission light spectrum, emitted from the first and second gemstones respectively are detected and analyzed, either independently or by comparison, to determine the relationship between the first and second gemstones. In some examples, data indicative of visible light absorbance or three-dimensional models of the gemstones is combined with the fluorescence data to determine the properties or the relationship.

Abstract: There are provided method for detecting inclusions in a gemstone comprising illuminating the gemstone by successively producing illumination patterns on the gemstone each selected so as to simultaneously provide an internal uniform illumination of one or more predetermined light exit regions of the gemstone, and each being defined by a unique combination of spaced apart light entrance areas illuminated simultaneously from corresponding illumination directions. The method further comprises capturing a plurality of images of the gemstone when illuminated as indicated above, processing the images and identifying inclusions in the images based on non-uniformities in the internal illumination detected in the images. The illumination patterns can be produced by an illumination system configured to selectively illuminate the spaced apart light entrance areas of the gemstone from corresponding illumination directions.

Abstract: There are provided method for detecting inclusions in a gemstone comprising illuminating the gemstone by successively producing illumination patterns on the gemstone each selected so as to simultaneously provide an internal uniform illumination of one or more predetermined light exit regions of the gemstone, and each being defined by a unique combination of spaced apart light entrance areas illuminated simultaneously from corresponding illumination directions. The method further comprises capturing a plurality of images of the gemstone when illuminated as indicated above, processing the images and identifying inclusions in the images based on non-uniformities in the internal illumination detected in the images. The illumination patterns can be produced by an illumination system configured to selectively illuminate the spaced apart light entrance areas of the gemstone from corresponding illumination directions.

Abstract: A computerized system, kit and method for producing an accurate 3D-Model of a gemstone by obtaining an original 3D-model of an external surface of the gemstone; imaging at least one selected junction with only portions of its associated facets and edges disposed adjacent the junction, the location of the junction being determined based on information obtained at least partially by using the original 3D model; analyzing results of the imaging to obtain information regarding details of the gemstone at the junction; and using the information for producing an accurate 3D-model of said external surface of the gemstone, which is more accurate than the original 3-D model.