HPHT synthetic diamond identification method and identification system

Abstract

This invention provides a method, system, and storage medium for identifying HPHT synthetic diamonds, belonging to the field of gemstone testing technology. By combining X-ray fluorescence spectroscopy, deuterium lamp electroluminescence spectroscopy, and laser photoluminescence spectroscopy, it can distinguish natural diamonds from HPHT synthetic diamonds, improving the accuracy of HPHT synthetic diamond identification. Furthermore, this identification method, based on the optical defect characteristics of HPHT synthetic diamonds, provides a fast and effective systematic detection process, enhancing the authority and technological advancement of testing institutions and safeguarding the sustainable development of the diamond-related industry.

Description

Technical Field

[0001] The present invention belongs to the technical field of gemstone detection, and in particular relates to an identification method and an identification system for HPHT synthetic diamonds. Background Art

[0002] There are two methods for producing large, gem-quality synthetic diamonds: high-pressure, high-temperature (HPHT) and chemical vapor deposition (CVD). The former mimics the natural formation process of diamonds, dissolving a carbon source (graphite or diamond powder) in a metal catalyst under high-temperature and high-pressure conditions (pressure: 4.8-6.0 GPa, temperature: 1100-1500°C), followed by crystallization along the cooler side of the reaction chamber. In the early days of HPHT synthesis technology, traditional gemological detection methods such as 10x magnification, microscopes, and polarizing filters could distinguish HPHT synthetic diamonds from natural diamonds by observing metal catalyst inclusions, color banding, and anomalous birefringence.

[0003] However, with the advancement of synthetic technology and the expansion of production scale, existing technologies have enabled the production of large, high-clarity, high-color HPHT synthetic diamonds. The highest-quality examples have achieved clarity levels of DE and VVS. These high-color and high-clarity HPHT synthetic diamonds present new challenges in identification, particularly in terms of testing equipment costs, personnel skills, and time. Currently, the detection of HPHT synthetic diamonds relies primarily on optical phenomena generated by the interactions of impurity elements and defects introduced during the preparation and growth of HPHT synthetic diamonds. However, current domestic research on the fundamental optical characteristics of HPHT synthetic diamonds, as well as the interpretation and characterization of their typical luminescence characteristics, is limited. There is also no publicly available or systematic testing process.

[0004] Therefore, it is urgent to propose a fast and effective HPHT synthetic diamond detection technology and process to enhance the authority and technological advancement of detection institutions and maintain the sustainable development of diamond-related industries. Summary of the Invention

[0005] The purpose of the present invention is to address the above-mentioned deficiencies in the prior art and provide a method and system for identifying HPHT synthetic diamonds.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] The first object of the present invention is to provide a method for identifying HPHT synthetic diamonds, comprising the steps of:

[0008] S1. Using Fourier transform infrared spectroscopy to determine whether it is an HPHT synthetic diamond: if it has the infrared spectral characteristics of IaA, IaB and IaAB, then it is determined to be a non-HPHT synthetic diamond; if not, proceed to step S2;

[0009] S2. Using a diamond viewing instrument, determine whether the diamond has symmetrical square and diagonal patterns and blue-green phosphorescence. If so, it is determined to be an HPHT synthetic diamond; if not, proceed to step S3.

[0010] S3, using X-ray fluorescence spectroscopy to determine whether the diamond has the characteristic Kα fluorescence peaks of Fe, Ti, and Co; if the determination result is yes, the diamond to be tested is an HPHT synthetic diamond; if the determination result is no, proceeding to step S4;

[0011] S4, using deuterium lamp electroluminescence spectrum detection to determine whether there is a 490nm central blue-green emission peak, if the determination result is yes, proceed to step S5; if the determination result is no, proceed to step S6;

[0012] S5, using deuterium lamp electroluminescence spectrum detection to determine whether there is a 590nm central emission peak. If the determination result is yes, the diamond to be tested is an HPHT synthetic diamond; if the determination result is no, proceed to step S6;

[0013] S6, using a 532 nm laser photoluminescence spectrum to determine whether there are 883 nm peaks and 884 nm peaks. If the determination result is yes, the diamond to be tested is an HPHT synthetic diamond; if the determination result is no, proceed to step S7;

[0014] S7. Using a 325 nm laser photoluminescence spectrum, determine whether the diamond has peaks at 483.6 nm, 483.9 nm, 484.2 nm, and 484.5 nm. If the determination result is yes, the diamond is an HPHT synthetic diamond; if the determination result is no, the diamond is not a HPHT synthetic diamond.

[0015] Furthermore, the detection parameters of the X-ray fluorescence spectrum are: filter conditions Mid Za, Mid Zb, and spectral range 0-40 keV.

[0016] Based on the Kα fluorescence peak positions of Ti, Fe, Co, and Ni: Kα 4.508 keV, Kβ 4.932 keV of Ti; Kα 6.398 keV, Kβ 7.058 keV of Fe; Kα 6.924 keV, Kβ 7.648 keV of Co; Kα 7.472 keV, Kβ 8.264 keV of Ni.

[0017] Furthermore, the detection parameters of the deuterium lamp electroluminescence spectrum are: using an ultraviolet deuterium lamp light source, preferably irradiating the sample in the range of 200-230 nm, using a Y-type ultraviolet light line to connect the sample, the light source and the inductively coupled detector (preferably with a pixel of 1044×64 or above), and the acquisition parameters are determined according to the actual kinetic characteristics of blue-green and orange-red phosphorescence, preferably with an integration time of more than 1 msec, an integration interval of more than 1 msec, and a spectral range of more than 350-750 nm.

[0018] Furthermore, the detection parameters of the laser photoluminescence spectrum are: equipped with a 532 nm green laser light source with a power of 10 mW or more and a spectral range of 540-900 nm; and a 325 or 355 nm ultraviolet laser light source with a power of 10 mW or more; an integration time of 1 sec or more, an integration number of 2 times or more, and a spectral range of 360-900 nm.

[0019] Furthermore, the method also includes collecting the Fourier transform infrared spectrum of the diamond to be tested, and using a micro-focused light source to perform spectral measurement using a transmission method or a reflection method for faceted diamonds.

[0020] Furthermore, the Fourier transform infrared spectroscopy detection parameters are: resolution of 4 cm -1 and below, spectral range 4000-600 cm -1 .

[0021] Furthermore, the Fourier transform infrared spectrum of the HPHT synthetic diamond includes type IIa, type IIb and type Ib.

[0022] Furthermore, when observed using a diamond viewing instrument, if the diamond has symmetrical square and diagonal patterns and blue-green phosphorescence, it is determined to be an HPHT synthetic diamond.

[0023] A second object of the present invention is to provide a system for identifying HPHT synthetic diamonds. The system is based on the above-mentioned HPHT synthetic diamond identification method and includes at least:

[0024] The system implements the above-mentioned HPHT synthetic diamond identification method, and at least includes:

[0025] a data acquisition module configured to obtain Fourier transform infrared spectrum data, crystal morphology, X-ray fluorescence spectrum data, and photoluminescence spectrum data of the diamond to be tested;

[0026] The first discrimination module is configured to use Fourier transform infrared spectroscopy to determine whether it is an HPHT synthetic diamond: if it has IaA, IaB and IaAB infrared spectral characteristics, it is judged to be non-HPHT synthetic diamond; if not, it enters the second discrimination module;

[0027] The second identification module is configured to use a diamond viewing instrument to observe and determine whether the diamond has symmetrical square and diagonal patterns and blue-green phosphorescence. If so, it is identified as an HPHT synthetic diamond; if not, it enters the third identification module;

[0028] The third discrimination module is configured to use X-ray fluorescence spectroscopy to determine whether the diamond has the Kα characteristic fluorescence peaks of Fe, Ti, and Co. If so, it is judged to be an HPHT synthetic diamond; if not, it enters the fourth discrimination module;

[0029] The fourth discrimination module is configured to use the deuterium lamp electroluminescence spectrum to determine whether it has a 490nm central blue-green emission peak. If so, it enters the fifth discrimination module; if not, it enters the sixth discrimination module;

[0030] The fifth discrimination module is configured to use deuterium lamp electroluminescence spectrum to determine whether the diamond has a central emission peak of 590nm. If so, it is judged to be an HPHT synthetic diamond; if not, the sixth discrimination module is entered;

[0031] The sixth discrimination module is configured to use a 532nm laser photoluminescence spectrum to determine whether there are 883nm peaks and 884nm peaks. If so, it is determined to be an HPHT synthetic diamond; if not, it enters the seventh discrimination module;

[0032] The seventh identification module is configured to use a 325 nm laser photoluminescence spectrum to determine whether there are peaks at 483.6 nm, 483.9 nm, 484.2 nm, and 484.5 nm. If so, it is identified as an HPHT synthetic diamond; if not, it is identified as a non-HPHT synthetic diamond.

[0033] A third object of the present invention is to provide a computer-readable storage medium storing a program, wherein the program can be executed by one or more processors to implement the above-mentioned method for identifying HPHT synthetic diamonds.

[0034] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0035] (1) The present invention provides a method, system, and storage medium for identifying HPHT synthetic diamonds. These methods utilize X-ray fluorescence spectroscopy, deuterium lamp electroluminescence spectroscopy, and laser photoluminescence spectroscopy to distinguish natural diamonds from HPHT synthetic diamonds, thereby improving the accuracy of HPHT synthetic diamond identification. Furthermore, the identification method, based on the systematic detection process of the optical defect characteristics of HPHT synthetic diamonds, is fast and effective, enhancing the authority and technological advancement of testing institutions and safeguarding the sustainable development of the diamond-related industry.

[0036] (2) The present invention also provides a detailed characterization and quantitative analysis of blue-green and orange-red phosphorescence, and describes a specific testing method, providing new identification features for the rapid identification of HPHT synthetic diamonds. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic flow chart of a method for identifying HPHT synthetic diamonds provided by the present invention;

[0038] Figure 2 This is the infrared absorption spectrum of type IIa diamond, where only the intrinsic peak of diamond is visible;

[0039] Figure 3a This is the infrared absorption spectrum of type IaA diamond;

[0040] Figure 3b This is the infrared absorption spectrum of type IaB diamond;

[0041] Figure 3c This is the infrared absorption spectrum of type Ib diamond;

[0042] Figure 4a This is the infrared absorption spectrum of nearly colorless type IIb diamond;

[0043] Figure 4b This is the infrared absorption spectrum of blue type IIb diamond;

[0044] Figure 5 HPHT synthetic near-colorless diamonds at DiamondView TM The blue-green phosphorescence observed under different exposure acquisition times;

[0045] Figure 6 HPHT synthetic near-colorless diamonds at DiamondView TM Green fluorescence and blue-green phosphorescence observed under the

[0046] Figure 7 HPHT synthetic near-colorless diamonds at DiamondView TM Green fluorescence, orange-red fluorescence and blue-green phosphorescence observed under the microscope;

[0047] Figure 8 This is the XRF spectrum of HPHT synthetic diamond (Mid Zb band cutoff 0-10 keV);

[0048] Figure 9 This is the emission spectrum of blue-green phosphorescence in HPHT synthesis;

[0049] Figure 10 This is the emission spectrum of orange-red phosphorescence in HPHT synthesis;

[0050] Figure 11 This is the 483 nm series of spectral peaks of the 325 nm laser photoluminescence spectrum related to Ni in HPHT synthetic diamonds;

[0051] Figure 12 The 883 / 884nm double peak diagram of the Ni-related 532nm laser photoluminescence spectrum in HPHT synthetic diamond;

[0052] Figure 13 This is a schematic diagram of the structure of a HPHT synthetic diamond identification system provided by the present invention. DETAILED DESCRIPTION

[0053] To make the objectives, technical solutions, and advantages of the present invention more apparent, the following describes the specific embodiments of the present invention in further detail with reference to specific examples and accompanying drawings. Where specific techniques or conditions are not specified in the examples, the techniques or conditions described in the literature in the art or in the product instructions shall prevail.

[0054] Unless otherwise specified, the raw materials, equipment and methods used in the present invention are commonly used in the art.

[0055] In some embodiments, unless the diamond has obvious visible catalyst inclusions or is a rough HPHT synthetic diamond, it is difficult to identify the HPHT synthetic diamond directly by the naked eye and requires detection using conventional gemological instruments and large instruments.

[0056] In some embodiments, HPHT synthetic diamond rough and lower-quality HPHT synthetic diamond facets can be quickly identified using traditional gemological instruments such as a 10x magnifying glass, a gemological microscope, and a polarizing filter. Key identification features include typical HPHT synthetic diamond growth characteristics, inclusions, and polarization characteristics.

[0057] In some embodiments, faceted HPHT synthetic diamonds of high synthetic quality and near-transparent interiors are often indistinguishable from natural diamonds using the aforementioned traditional gemological identification methods. In such cases, non-destructive testing is primarily performed using various large-scale instruments to detect trace element impurities and related optical defects introduced during the preparation and growth processes of HPHT synthetic diamonds.

[0058] The main instruments and equipment used include: Fourier transform infrared spectrometer (FTIR), DiamondView TM , GV5000, etc.), X-ray fluorescence spectrometer (XRF), photoluminescence spectrometer (PL).

[0059] Example 1

[0060] like Figure 1 As shown, HPHT synthetic diamonds with high clarity and high color grade that are difficult to directly judge by naked eye observation or microscopic magnification observation can be identified by applying the HPHT synthetic diamond identification method process of the present invention. The identification process is as follows:

[0061] 1. Use Fourier transform infrared spectroscopy to determine the type of diamond and narrow the scope of HPHT synthetic diamond identification.

[0062] Infrared light refers to the wavelength range between visible light and microwaves (12800-10 cm -1 ) electromagnetic waves, which can be subdivided into near-infrared light (12800-4000 cm -1 ), mid-infrared light (4000-400 cm -1 ) and far infrared (400-10cm -1 Different substances have different structures and elemental compositions, resulting in different positions and magnitudes of infrared absorption peaks. Therefore, measuring a substance's infrared spectrum can be used to determine its type and concentration. Infrared spectroscopy plays a crucial role in diamond detection. By measuring its absorption or reflection spectrum, it is possible to identify the diamond's phase and determine its type.

[0063] like Figure 2 The absorption spectrum of pure diamond is shown in the figure. It can be seen that diamond has an absorption spectrum of 2665-2380 cm -1 , and 2610, 2030, 1974 cm -1 This type of diamond without nitrogen and boron related defects is called type IIa diamond.

[0064] like Figures 3a-3c As shown in Figure 2, if there are nitrogen-related defects in diamond, the diamond will be at 1000-1350 cm -1 A variety of infrared spectral features related to nitrogen appear within the range. Based on the composition of nitrogen, it can be subdivided into three main luminescent defects: A-center, B-center, and C-center.

[0065] The A center has a wavelength of 1282 cm in the infrared spectrum. -1 The diamond with only the A center spectral characteristic is called type IaA diamond; the B center is at 1175 cm -1 Diamonds with only the B-center spectrum characteristics are called IaB diamonds, while diamonds with both A-center and B-center spectrum characteristics are classified as IaAB diamonds; the C-center is at 1344 and 1130 cm -1 Diamonds with an absorption peak at the C center and only C-center spectral characteristics are called type Ib diamonds.

[0066] like Figure 4a-4bAs shown, the boron-related defects in diamond are at 2930, 2802, and 2458 cm -1 There is an absorption peak near 2900 cm -1 Diamonds with these spectral characteristics are classified as type IIb diamonds.

[0067] Most natural diamonds contain small amounts of nitrogen-related defects. Over a long geological process, these nitrogen defects migrate and spread, forming A- and B-centered defects. Consequently, the infrared spectra of natural diamonds are primarily those of types IaA, IaB, and IaAB, with only a few exhibiting the FTIR spectral characteristics of types Ib, IIa, and IIb. HPHT synthetic diamonds, on the other hand, are the opposite. Currently, the near-colorless HPHT synthetic diamonds on the market are primarily types IIa, IIb, and Ib. Consequently, HPHT synthetic diamonds primarily exhibit the FTIR spectral characteristics of types IIa, IIb, and Ib, with no other diamond types observed. Near-colorless diamonds, in particular, exhibit only the FTIR characteristics of types IIa or IIb.

[0068] Testing Method: For diamond samples that cannot be directly identified through traditional gemological observation, this testing method first cleans the sample to remove surface oils and other contaminants. The diamond is then placed in the optical path of an infrared spectrometer with an air background measurement. The diamond's spatial position within the optical path is fine-tuned. By examining the infrared spectral signal and interferogram, the diamond's intrinsic infrared peaks are identified in the FTIR spectrum. Based on the collected infrared spectrum, the method screens for characteristic absorption peaks in the FTIR according to the aforementioned testing principles. Diamonds with FTIR spectral characteristics other than Type IaA, IaB, or IaAB are selected for further testing.

[0069] 2. Use a diamond observer to observe whether it has symmetrical squares, diagonal lines and blue-green phosphorescence.

[0070] A diamond viewer uses ultraviolet light close to the diamond band gap width (≤230 nm) to illuminate diamonds, stimulating photoluminescence. This light is then magnified and observed using a camera. It is used to capture fluorescence and phosphorescence images of diamond samples. By adjusting the integration time, gain, spot size, and delay time, the device can observe the intensity, color, and spatial distribution of the diamond's photoluminescence. It is a quick and easy way to distinguish natural from synthetic diamonds.

[0071] Detection Method: Diamonds that do not exhibit the characteristics of type IaA, IaB, or IaAB diamonds during FTIR testing require observation with a diamond viewer. The luminescence pattern is then judged based on its color and spatial distribution. First, the surface of the diamond sample is cleaned to remove any fluorescent organic matter, such as plasticine and blu-tack, that may have been contaminated during FTIR testing. The sample is then placed on the sample stage of the diamond viewer and its relative position within the viewer's lens is fine-tuned using the adjustment knob. The diamond viewer's exposure time, gamma value, spot size, and gain are adjusted in both fluorescence and phosphorescence modes. Images are captured after achieving the desired clarity, brightness, and contrast. Finally, the captured diamond images are observed. Typical HPHT synthetic diamonds, when viewed under a diamond viewer, exhibit luminescence characteristics characterized by a crystallization habit of octahedral and cubic growth. Blocky, hourglass-shaped luminescence patterns, and seed crystal growth areas are common in faceted diamonds. HPHT synthetic diamonds exhibit a rich variety of luminescence colors, and the same sample often exhibits more than one color. The distribution of these colors varies depending on the growth region. Among the nearly colorless and blue HPHT synthetic diamonds, they are mainly distributed in different growth areas with varying degrees of blue, blue-green, and green-blue. The color difference is generally small (e.g. Figure 5 and Figure 6 In yellow HPHT synthetic diamonds, green, yellow-green, blue-green, and orange-red luminescence are common, distributed along the octahedron, cube, and their junctions (as shown in Figure 7 shown).

[0072] Diamond samples that do not have identifiable luminescence characteristics, or do not emit light or have blue-green phosphorescence characteristics, need to undergo XRF, xenon lamp photoluminescence spectroscopy (Xenon-PL), and laser photoluminescence spectroscopy (Laser-PL) to quantitatively analyze and judge the trace elements, weak luminescence characteristics, and non-intrinsic luminescence characteristics.

[0073] 3. Use X-ray fluorescence spectroscopy to determine whether it has the Kα characteristic fluorescence peaks of Fe, Ti, and Co.

[0074] When X-rays of appropriate energy (wavelength) strike a material, the inner-shell electrons of atoms are excited to jump to higher-energy orbitals or break free from their atomic bonds, creating vacancies. Electrons in outer-shell orbitals fill these vacancies, emitting secondary X-rays. The energy and intensity of these secondary X-rays depend on the type and concentration of the corresponding atoms. Therefore, this device can be used to measure some impurity elements in HPHT synthetic diamonds. Catalysts such as Fe, Ni, and Co are often added during the HPHT synthesis process. For near-colorless diamonds, Ti and Al are also added as nitrogen scavengers. These elements can remain in the diamond as inclusions or impurity defects, and their concentrations are generally low in natural diamonds.

[0075] Detection method: Place the diamond sample after fluorescence observation in front of the X-ray tube of the X-ray fluorescence spectrometer. Use the observation lens to manually adjust the sample position to ensure that the diamond sample covers the area where the X-ray spot is located. Select MidZa and / or MidZb filters and perform XRF acquisition in the 0-40 keV range. The acquisition time and dead time are adjusted according to the actual test conditions. Based on the specific position of the Kα and Kβ fluorescence peaks in the energy spectrum, look up the table to determine whether the diamond sample has the corresponding X-ray fluorescence peaks of the relevant impurity elements (such as Figure 8 If yes, it is identified as HPHT synthetic diamond; if not, it goes to the next step of identification.

[0076] 4. Use deuterium lamp electroluminescence spectrum to determine whether it has a blue-green emission peak at the center of 490nm.

[0077] Photoluminescence originates from the de-excitation process of defects in a material after being excited by an external light source. Ground-state electrons can be excited by external light of a specific wavelength, absorbing energy and transitioning from the ground state to an excited state. They then spontaneously return to the ground state, releasing some of this energy through radiative transitions. Defects in diamond often absorb ultraviolet and visible light of varying wavelengths, emitting corresponding photoluminescence, primarily zero-phonon lines and phonon sidebands.

[0078] The blue-green and orange-red phosphorescence in HPHT synthetic diamonds can be quantified using a continuous wavelength xenon lamp and monochromatic light of a specific wavelength that has been treated. This method is primarily used to detect samples that lack the typical HPHT synthetic diamond characteristics or the blue-green phosphorescence characteristic when viewed with a diamond viewer.

[0079] like Figure 9 As shown, for samples lacking the typical luminescence pattern characteristic of HPHT synthetic diamonds, a deuterium lamp with a power distribution in the 215-230 nm range or a monochromatic 225 nm xenon lamp was used to illuminate the diamond samples. For deuterium lamps with a continuous power distribution, the blue-green photoluminescence produced by the samples after intrinsic excitation was collected using an inductively coupled detector; for monochromatic xenon lamps, the blue-green photoluminescence produced by the samples was collected using a photomultiplier tube. The spectra exhibited bilateral asymmetry, with a broad emission peak centered between 480 and 500 nm. For other samples lacking the characteristic xenon lamp photoluminescence, laser photoluminescence spectroscopy was required.

[0080] 5. Use deuterium lamp electroluminescence spectrum to determine whether it has a central emission peak at 590nm.

[0081] For diamond samples that only have blue-green fluorescence but not blue-green phosphorescence, use a deuterium lamp with power distribution in the range of 230-370 nm, or a monochromatic xenon lamp at 254 nm and 365 nm to irradiate the diamond sample. The results are as follows: Figure 10 As shown in the figure. For a deuterium lamp with a continuous power distribution, an inductively coupled detector is used to collect the blue-green photoluminescence produced by the sample after intrinsic excitation. For a monochromatic xenon lamp, a photomultiplier tube is used to collect the orange-red photoluminescence produced by the sample under ultraviolet light. If the spectrum shows a broad emission peak centered at 580-590 nm, it is identified as an HPHT synthetic diamond. If not, the next step of identification is carried out.

[0082] 6. Use 532 nm laser photoluminescence spectroscopy to determine whether there are 883 nm and 884 nm peaks.

[0083] Using a highly monochromatic, relatively high-power monochromatic laser, it is possible to excite and detect other extremely minute luminescent defects in sampled diamonds. This method is primarily used to assist in the identification of HPHT synthetic diamonds, as well as a small number of acceptable diamonds that lack any luminescent characteristics.

[0084] Testing Method: For diamond samples that do not show luminescence in a diamond observation instrument or xenon lamp electroluminescence spectrometer, the presence of Ni-related defects and intrinsic structural defects can be determined by analyzing their photoluminescence spectra. After cleaning, the diamond sample is placed on a custom-made heat-conducting sample stage with a built-in copper sheet. The heat-conducting sample stage contains liquid nitrogen at approximately 77 K. After being cooled to approximately 77 K by the copper sheet, the sample, along with the heat-conducting sample stage, is placed on the laser photoluminescence spectrometer stage. After fine-tuning the focus, Raman and photoluminescence spectra are collected within an appropriate integration time and number of measurements.

[0085] like Figure 11 As shown in the figure, Ni-related defects are a series of peaks (883.2 and 884.8 nm) at 884 nm excited by 532 nm. These Ni-related defects originate from the Fe-Ni catalyst added during the high-temperature and high-pressure synthesis process.

[0086] If yes, it is identified as HPHT synthetic diamond; if not, proceed to the next step of identification;

[0087] 7. Use 325 nm laser photoluminescence spectrum to determine whether there are peaks at 483.6 nm, 483.9 nm, 484.2 nm and 484.5 nm.

[0088] like Figure 12As shown, Ni-related defects are a series of peaks at 483 nm (483.6, 483.9, 484.2, and 484.5 nm) excited at 325 nm.

[0089] If yes, it is identified as HPHT synthetic diamond; if no, it is identified as non-HPHT synthetic diamond.

[0090] Example 2

[0091] This embodiment, based on the design of embodiment 1, discloses a system for identifying HPHT synthetic diamonds. Figure 13 As shown, the system is based on the above-mentioned HPHT synthetic diamond identification method and includes at least:

[0092] a data acquisition module configured to obtain Fourier transform infrared spectrum, crystal morphology, X-ray fluorescence spectrum, and photoluminescence spectrum data of the diamond to be tested;

[0093] The first discrimination module is configured to use Fourier transform infrared spectroscopy to determine whether it is an HPHT synthetic diamond: if it has IaA, IaB and IaAB infrared spectral characteristics, it is judged to be non-HPHT synthetic diamond; if not, it enters the second discrimination module;

[0094] The second identification module is configured to use a diamond viewing instrument to observe and determine whether the diamond has symmetrical square and diagonal patterns and blue-green phosphorescence. If so, it is identified as an HPHT synthetic diamond; if not, it enters the third identification module;

[0095] The third discrimination module is configured to use X-ray fluorescence spectroscopy to determine whether the diamond has the Kα characteristic fluorescence peaks of Fe, Ti, and Co. If so, it is judged to be an HPHT synthetic diamond; if not, it enters the fourth discrimination module;

[0096] The fourth discrimination module is configured to use the deuterium lamp electroluminescence spectrum to determine whether it has a 490nm central blue-green emission peak. If so, it enters the fifth discrimination module; if not, it enters the sixth discrimination module;

[0097] The fifth discrimination module is configured to use deuterium lamp electroluminescence spectrum to determine whether the diamond has a central emission peak of 590nm. If so, it is judged to be an HPHT synthetic diamond; if not, the sixth discrimination module is entered;

[0098] The sixth discrimination module is configured to use a 532nm laser photoluminescence spectrum to determine whether there are 883nm peaks and 884nm peaks. If so, it is determined to be an HPHT synthetic diamond; if not, it enters the seventh discrimination module;

[0099] The seventh identification module is configured to use a 325nm laser photoluminescence spectrum to determine whether there are peaks at 483.6nm, 483.9nm, 484.2nm, and 484.5nm. If so, it is identified as an HPHT synthetic diamond; if not, it is identified as a non-HPHT synthetic diamond.

[0100] Example 3

[0101] This embodiment, based on the design of Embodiments 1 and 2, discloses a computer-readable storage medium storing a program that can be executed by one or more processors to implement the above-mentioned HPHT synthetic diamond identification method.

[0102] In the absence of conflict, the above embodiments and features in the embodiments may be combined with each other.

[0103] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for identifying HPHT synthetic diamonds, comprising: The following steps are involved: S1. Using Fourier transform infrared spectroscopy to determine whether it is an HPHT synthetic diamond: if it has the infrared spectral characteristics of IaA, IaB and IaAB, then it is determined to be a non-HPHT synthetic diamond; if not, proceed to step S2; S2. Using a diamond viewing instrument, determine whether the diamond has symmetrical square and diagonal patterns and blue-green phosphorescence. If so, it is determined to be an HPHT synthetic diamond; if not, proceed to step S3. S3. Using X-ray fluorescence spectroscopy to determine whether there are Kα characteristic fluorescence peaks of Fe, Ti, and Co; If the determination result is yes, the diamond to be tested is an HPHT synthetic diamond; if the determination result is no, proceed to step S4; S4, using deuterium lamp electroluminescence spectrum detection to determine whether there is a 490nm central blue-green emission peak. If the determination result is yes, proceed to step S5; When the determination result is no, proceed to step S6; S5, using deuterium lamp electroluminescence spectrum detection to determine whether there is a 590nm central emission peak. If the determination result is yes, the diamond to be tested is an HPHT synthetic diamond; if the determination result is no, proceed to step S6; S6, using a 532 nm laser photoluminescence spectrum to determine whether there are 883 nm peaks and 884 nm peaks. If the determination result is yes, the diamond to be tested is an HPHT synthetic diamond; if the determination result is no, proceed to step S7; S7. Using a 325 nm laser photoluminescence spectrum, determine whether the diamond has peaks at 483.6 nm, 483.9 nm, 484.2 nm, and 484.5 nm. If the determination result is yes, the diamond is an HPHT synthetic diamond; if the determination result is no, the diamond is not a HPHT synthetic diamond.

2. The method according to claim 1, wherein The detection parameters of the X-ray fluorescence spectrum are: filter conditions Mid Za, Mid Zb, and spectral range 0-40 keV.

3. The method according to claim 1, wherein The detection parameters of the deuterium lamp electroluminescence spectrum are as follows: using an ultraviolet deuterium lamp light source of 200-230 nm to irradiate the sample, using a Y-shaped ultraviolet light line to connect the sample, light source and inductively coupled detector, and the acquisition parameters are determined according to the actual kinetic characteristics of blue-green and orange-red phosphorescence.

4. The method according to claim 1, wherein The detection parameters of the laser photoluminescence spectrum are equipped with a 532 nm green laser light source with a power of more than 10 mW and a spectral range of 540-900 nm; and a 325 or 355 nm ultraviolet laser light source with a power of more than 10 mW and a spectral range of 360-900 nm.

5. The method according to claim 1, wherein It also involves collecting a Fourier Transform Infrared spectrum of the diamond being tested.

6. The method according to claim 5, wherein The Fourier transform infrared spectroscopy detection parameter is a resolution of 4 cm -1 and below, spectral range 4000-600 cm -1 .

7. The method according to claim 5, wherein The Fourier transform infrared spectrum of the HPHT synthetic diamond includes type IIa, type IIb and type Ib.

8. The method according to claim 5, wherein Further observation using a diamond viewing instrument shows that if the diamond has symmetrical square and diagonal patterns and blue-green phosphorescence, it is determined to be an HPHT synthetic diamond.

9. A system for identifying HPHT synthetic diamonds, characterized in that: The system implements the HPHT synthetic diamond identification method described in claim 8, and at least includes: a data acquisition module configured to obtain Fourier transform infrared spectrum data, crystal morphology, X-ray fluorescence spectrum data, and photoluminescence spectrum data of the diamond to be tested; The first discrimination module is configured to use Fourier transform infrared spectroscopy to determine whether it is an HPHT synthetic diamond: if it has IaA, IaB and IaAB infrared spectral characteristics, it is judged to be non-HPHT synthetic diamond; if not, it enters the second discrimination module; The second identification module is configured to use a diamond viewing instrument to observe and determine whether the diamond has symmetrical square and diagonal patterns and blue-green phosphorescence. If so, it is identified as an HPHT synthetic diamond; if not, it enters the third identification module; The third discrimination module is configured to use X-ray fluorescence spectroscopy to determine whether the diamond has the Kα characteristic fluorescence peaks of Fe, Ti, and Co. If so, it is judged to be an HPHT synthetic diamond; if not, it enters the fourth discrimination module; The fourth discrimination module is configured to use the deuterium lamp electroluminescence spectrum to determine whether it has a 490nm central blue-green emission peak. If so, it enters the fifth discrimination module; if not, it enters the sixth discrimination module; The fifth discrimination module is configured to use deuterium lamp electroluminescence spectrum to determine whether the diamond has a central emission peak of 590nm. If so, it is judged to be an HPHT synthetic diamond; if not, the sixth discrimination module is entered; The sixth discrimination module is configured to use a 532 nm laser photoluminescence spectrum to determine whether there are 883 nm peaks and 884 nm peaks. If so, it is determined to be an HPHT synthetic diamond; if not, the seventh discrimination module is entered; The seventh identification module is configured to use a 325 nm laser photoluminescence spectrum to determine whether there are peaks at 483.6 nm, 483.9 nm, 484.2 nm, and 484.5 nm. If so, it is identified as an HPHT synthetic diamond; if not, it is identified as a non-HPHT synthetic diamond.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a program, and the program can be executed by one or more processors to implement the HPHT synthetic diamond identification method according to any one of claims 1 to 8.

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