Method and systems are presented for authentication of precious stones, according to their natural ID and/or predetermined markings created in the stones, based on unique characteristic radiation response of the stone to predetermined primary radiation.

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

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.

Methods, apparatus, and systems for fabricating diffractive structures on gemstones for high optical performance are provided. In one aspect, a method includes obtaining a plurality of gemstone characteristics of a gemstone, determining that the gemstone exhibits each of the plurality of gemstone characteristics within a respective predetermined range, identifying a diffractive structure setting associated with a combination of the respective predetermined ranges for the plurality of gemstone characteristics, and fabricating diffractive structures on the gemstone according to the diffractive structure setting.

Methods and systems are provided for facilitating comparison of gemstones having multiple attributes that characterize the gemstones. A facilitated comparison system receives from a user a selection of a gemstone in a collection of the gemstones. Each gemstone in the collection is associated with a selling index indicating a probability of the gemstone being bought by a customer. For each of a predetermined set of the attributes, the system determines one or more comparable ranges. The system identifies alternate gemstones to recommend using the comparable ranges for the attributes and the selling indices of the gemstones. The system displays to the user the selected gemstone and one or more of the alternate gemstones for comparison.

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).

Systems and methods here may be configured for cooling and examining materials. In some example embodiments, the system may include a main thermoconductive body with indentations on the top surface, a bottom surface having legs structures along the edge, wherein the bottom surface and the plurality of leg structures form a partially enclosed bottom chamber, and a center channel connecting the top surface and the bottom chamber.

A system (100a) for determining the type of a diamond (130a), the system (100a) comprising a plurality of lasers (110a,120a) for directing light towards a diamond (130a), wherein each laser is of a different wavelength of light; wherein the spectrum of light from the plurality of lasers (110a,120a) extends from ultra-violet to near infra-red; a spectrometer (140a) for collecting luminescence spectrum from the diamond (130a) responsive to inhomogeneities upon light from the lasers (110a,120a) being directed towards the diamond (130a); a processor module (150a) for comparing photoluminescence spectrum collected by the spectrometer (140a) with pre-existing photoluminescence spectrum of known diamond type; and an output module (160a) for providing an output signal indicative of the diamond type of the diamond (130a), upon a predetermined threshold of correlation between the photoluminescence spectrum from the diamond (130a) and the pre-existing photoluminescence spectrum from the diamond (130a) and the pre-existing photoluminescence spectrum responsive to inhomogeneities of known diamond type.

THIS INVENTION relates to a method of or system for detecting presence of diamond in an object. The method comprises receiving classification data associated with photons emitted from object as a result of positron annihilation due to irradiation of the object with photons of a predetermined energy at which giant dipole resonance (GDR) occurs due to a nuclear reaction between the photons and carbon. The method then comprises the step of determining whether or not the object is potentially a diamond or diamondiferous by processing the received classification data with a trained machine-based learning classifier. The system typically implements the method described herein.

The application provides a gemstone testing apparatus for testing a specimen. The gemstone testing apparatus includes a handheld casing, a plurality of light sources, a test probe, a photodetector, a processor unit, and a display unit. The test probe is placed at one end of the handheld casing. A first end of the test probe is placed outside the handheld casing. The plurality of light sources is provided for emitting light rays towards an area that is in the vicinity of the first end. The first end is adapted for receiving light rays from the specimen and for transmitting the light rays to a second end of the test probe. The photodetector is arranged to measure an intensity of the light rays from the second end. The processor unit is provided for determining a material of the specimen in accordance to a measurement of the intensity of the light rays.