The application provides an improved gemstone testing device for testing a gemstone specimen. The device includes a housing, a platform for supporting the gemstone, a first light source for illuminating the gemstone, a second light source for exciting the gemstone, a third light source for exciting the gemstone, a light filter, a sheet of light absorptive material for absorbing blue light ray, a camera module for taking a picture of the gemstone, and a display module for displaying the picture and a corresponding reference picture of the gemstone to a user.

A pearl grading method includes the following steps: (1) determining the color type of the pearl to be graded; (2) generating a simulated three-dimensional graph of the pearl to be graded; (3) calculating roundness, so as to obtain a roundness grade; (4) calculating the diameter of the simulated three-dimensional graph, so as to obtain a diameter grade; (5) drawing an illumination-wavelength reflection spectrum; (6) changing a detected part, and drawing an illumination-wavelength reflection spectrum again; (7) repeating the step (6) for at least two times; (8) performing weighted average to obtain a correction curve; and (9) comparing the correction curve with each glossiness grade spectrum baseline, so as to determine a glossiness grade according to the spectrum baseline with the highest coincidence degree. The method has the beneficial effects of low cost, high speed, good result consistency and high detection precision.

Resonant Ultrasound Spectroscopy (RUS) is applied to diamonds (both cut/polished gemstones and rough diamonds) to yield a digital fingerprint from which the stone may be authenticated and sorted according to the structural quality. Diamonds are mined as rough stones from which they undergo examination to determine their value as being gem, or of two different industrial qualities. Fewer than 25% of mined diamonds are worthy of cutting and polishing to yield gems for jewelry. About 40% of the remaining population still have value as industrial diamonds for machine tools, and the rest is ground into dust to provide coatings for grinding applications. Rough stones exist in two conditions being coated and uncoated. The coated stones have a layer of polycrystalline diamond, different from the predominant crystal structure, rendering them opaque. This interferes with optical inspection, as any cracks, or inclusions can't be seen. RUS provides a reliable sorting and fingerprinting system for both cut/polished stones as well as rough diamonds of sufficient structural quality to yield a spectral signature. As high value items, diamonds are shipped around the world, and but sometimes thefts occur. RUS yields a digital fingerprint allowing the identity of an individual stone to be verified upon recovery.

A multi-functional precious stone testing apparatus includes a portable housing and a testing unit. The portable housing includes a portable housing having a hand-held casing and a probe casing extended from a front end of the hand-held casing. The testing unit housed in the hand-held casing includes a UV light emission unit, a UV light reflecting and guiding unit, and a UV light receiving unit. The UV light emission unit produces and emits both a long-wave UV light and a short-wave light, so as to allow the UV receiving unit to sense the UV lights reflected and refracted by a testing object for determining various qualities and distinguishing types of diamond of the testing object.

A magnifying device for jewelry and system for use of the same are disclosed. In one embodiment of the magnifying device, a securing ring is coupled to a body to selectively attach in a snap-fit engagement with a gem tester. A hinge assembly is also coupled to the body and a support frame is pivotally coupled thereto. A seat within the support frame defines a circular opening securing a magnifying lens therein. The support frame also includes a pivot blade extending therefrom that accepts rotational bearing force to cause the support frame and therefore the magnifying lens to rotate relative to the body.

A microstrip-type microwave sensor for the measurement of the dielectric properties of a solid or liquid material, constituted by a main line and two connected transmission lines integral at one of their extremities to the main line, the main line and two connected transmission lines being spaced from one another by a slot and being made integral with a substrate. The main line is connected to an electrical circuit by each of its two extremities to inject a sinusoidal signal, and wherein said main line has a width giving it an impedance in the range 50 Ohm, the two connected transmission lines being of the same width and of a length equal to one quarter of the wavelength guided in the substrate, the substrate having a height or thickness giving it flexibility or rigidity, the substrate being applied to a metallic support formed of a layer of metallic material.

The present invention relates to a method for non-destructive judgment of pearl quality by measuring the ultraviolet-visible reflectance spectrum and/or ultraviolet-visible fluorescence spectrum of a pearl or pearl shell to be inspected and comparing the values obtained with those preliminarily measured for a normal pearl or pearl shell. The present invention also relates to a non-destructive inspection apparatus of pearl quality. According to the present invention, the quality of the aimed pearl or pearl shell can be easily and rapidly judged under a non-destructive condition.

An ultrafast wide-field quantum sensing device using a neuromorphic event-based vision sensor includes a laser generating a laser beam; a dichroic mirror directing the laser beam onto a diamond sample and passing the laser beam reflected from the diamond, and an event camera receiving from the dichroic mirror the beam reflected from the diamond. A source of microwave energy applied to the diamond. A pulse generator synchronizes the microwave source and the event camera to create CW-ODMR measurements, wherein trigger pulses from the pulse generator are applied to the camera and microwave source. The optically detected magnetic resonance (ODMR) resonance frequency is determined based on the CW-ODMR measurements.

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.

A multi-functional precious stone testing apparatus includes a portable housing and a testing unit. The portable housing includes a portable housing having a hand-held casing and a probe casing extended from a front end of the hand-held casing. The testing unit housed in the hand-held casing includes a UV light emission unit, a UV light reflecting and guiding unit, and a UV light receiving unit. The UV light emission unit produces and emits both a long-wave UV light and a short-wave light, so as to allow the UV receiving unit to sense the UV lights reflected and refracted by a testing object for determining various qualities and distinguishing types of diamond of the testing object.