An apparatus (100) for identifying precious stones and man-made stones is disclosed. The apparatus (100) includes a handheld device (2) with a probe (4), a thermal and optical testing assembly, a microcontroller (36), and a visual indicator (6). The probe is electronically coupled with the handheld device (2) and is removable and replaceable. The probe (4) includes a copper tube (5a) with an optical fiber (23) and a tip (5) for contacting the stone under test. The thermal testing assembly heats the copper tube (5a) and the optical assembly illuminates the stone (12, 13) under test with UV light. The microcontroller (36) determines heat transfer and determines at least one of: the electrical, thermal, and optical properties of the stone. The microcontroller (36) identifies the type of stone, and the visual indicator displays the result.

Systems and methods here may be used for a setup of image capturing of a gemstone, such as a diamond, exposed to different light sources. Some examples utilize a setup that both sends light and captures the image through multiple dichroic beam splitters at pre-selected timing. The multiple light source and multiple dichroic beam splitter arrangement allows for multiple gemstones to be analyzed using multiple methods with minimal moving, changing, or adjusting the equipment for different samples.

A process for determining the type of a diamond having spin properties and physical properties, said process including the steps of: (i) determining the spin properties of a diamond of unknown type, using optically detected magnetic resonance to measure the spin properties of said diamond of an unknown type, wherein the spin properties are indicative of the physical properties of the diamond; (ii) comparing the spin properties of said unknown diamond with the spin properties of a plurality of diamonds of known types; and (iii) determining the type of said diamond of unknown type upon a predetermined threshold of correlation between the spin properties of said diamond of unknown type with the spin properties of a diamond of known type of said plurality of diamonds known types.

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.

A multi-functional precious stone testing apparatus includes a portable housing, a testing unit, and an indication unit. The portable housing includes a hand-held casing and a probe casing extended from a front end of the hand-held casing. The testing unit includes a conductive probe having a testing end portion extended out of a tip end of the probe casing for contacting a testing object to determine a conductivity of the testing object. The indication unit includes a LED light unit received in the hand-held casing for illuminating the testing end portion of the conductive probe during testing, wherein the LED light unit is positioned away from the tip end of the probe casing for preventing heat generated from the LED light unit being transmitted toward the conductive probe to affect an accurate measurement for the conductivity of the testing object.

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.

The embodiments disclosed herein relate to the examination of gemstones including diamonds, both cut/polished and rough, using the technology of Resonant Ultrasound Spectroscopy. The resonant frequencies are obtained by mechanically causing the stone to vibrate using a swept sine oscillator, sensing the resonance vibrations, and displaying the spectrum to yield a pattern describing the stone. The resonance fingerprints can be used to both track an individual stone to verify its integrity or to grade a rough stone to establish potential value.

A process for determining the type of a diamond having spin properties and physical properties, said process including the steps of: (i) determining the spin properties of a diamond of unknown type, using optically detected magnetic resonance to measure the spin properties of said diamond of an unknown type, wherein the spin properties are indicative of the physical properties of the diamond; (ii) comparing the spin properties of said unknown diamond with the spin properties of a plurality of diamonds of known types; and (iii) determining the type of said diamond of unknown type upon a predetermined threshold of correlation between the spin properties of said diamond of unknown type with the spin properties of a diamond of known type of said plurality of diamonds known types.

Systems and methods of quantum sensing include obtaining information regarding a target signal in electronic spin states of quantum defects in an ensemble of quantum defects, mapping the information regarding the target signal from the electronic spin states of the quantum defects to corresponding nuclear spin states associated with the quantum defects, applying a light pulse to the ensemble of quantum defects to reset the electronic spin states of the quantum defects, and repeating a readout stage a plurality of times within a readout duration. The readout stage includes mapping the information regarding the target signal back from the nuclear spin states to the corresponding electronic spin states and applying a data acquisition readout pulse to optically measure the electronic spin states of the quantum defects.

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.