Quantitative analysis method for occurrence state of gold in ore deposit

Abstract

This invention relates to the field of mineral analysis technology, specifically to a method for quantitative analysis of the occurrence state of gold in ore deposits. The method includes: pretreatment of ore samples to obtain the total gold content; gold hyper-enrichment treatment of the pretreated ore samples to obtain hyper-enriched ore samples; fabrication of resin targets for both the pretreated and hyper-enriched ore samples, and analysis of each resin target using TIMA; micro-area in-situ analysis of the sulfide resin targets using LA-ICP-MS; and quantitative analysis of the gold occurrence state in the ore samples using data obtained from TIMA and LA-ICP-MS analyses. Compared to traditional qualitative or semi-quantitative methods, this method has higher resolution and wider applicability, suitable for the study of different types of gold deposits, and provides reliable data support for subsequent optimization of beneficiation and smelting processes.

Description

Technical Field

[0001] This invention relates to the field of mineral analysis technology, and specifically to a method for quantitative analysis of the occurrence state of gold in mineral deposits. Background Technology

[0002] Gold in nature exists primarily in three states: visible gold, microscopic gold, and lattice gold. The study of gold occurrence states encompasses the types of gold minerals in ores, the proportions of different gold types, the grain size parameters of microscopic gold, and the types, grain sizes, and gold contents of gold-bearing minerals. Quantitatively identifying the occurrence states of gold in ore deposits is of significant scientific value for revealing the gold mineralization process and enrichment mechanisms, and also has important economic value for subsequent beneficiation and recovery.

[0003] However, research on the occurrence state of gold has long been limited to qualitative descriptions. The main research methods rely on microscopic identification of numerous thin sections, often requiring the selection of extremely high-grade samples, leading to insufficient sample representativeness. Furthermore, the analytical testing process is cumbersome, time-consuming, and labor-intensive. These problems are even more pronounced in the study of the occurrence state of low-grade associated gold in ore deposits, significantly increasing the research difficulty. Therefore, current research on the occurrence state of gold largely remains at the qualitative-semi-quantitative (estimation) level, failing to achieve precise quantitative techniques for determining the occurrence state of gold. Many researchers often conclude that gold mainly occurs in the form of lattice gold based on observations of thin sections. This simplistic qualitative description presents many difficulties for understanding the enrichment mechanism and mineralization process of gold in ore deposits. Summary of the Invention

[0004] To address the technical problem that existing technologies struggle to quantitatively analyze the occurrence state of gold in mineral deposits, this invention provides a method for quantitatively analyzing the occurrence state of gold in mineral deposits.

[0005] This invention employs the following technical solution: a method for quantitative analysis of the occurrence state of gold in mineral deposits, comprising the following steps: S1: Pre-treating ore samples and obtaining the total gold content in the ore samples; performing gold hyper-enrichment treatment on the pre-treated ore samples to obtain hyper-enriched ore samples: gold concentrate, sulfides, and silicates. S2: Preparing resin targets for both the pre-treated and hyper-enriched ore samples, and scanning each resin target using an automated mineral quantitative analysis system to obtain the mineral composition and mass fraction of gold-bearing minerals in the pre-treated ore samples, as well as the quantity, type, and particle size distribution of microscopic gold in the hyper-enriched ore samples. S3: Performing in-situ micro-area analysis on the hyper-enriched sulfide resin target using LA-ICP-MS to obtain the gold content in each gold-bearing mineral contained in the sulfides. S4: Multiply the gold content in any gold-bearing mineral by the mass fraction of the corresponding gold-bearing mineral in the ore sample, and then divide the product by the total gold content in the ore sample to obtain the proportion of gold in that gold-bearing mineral in the ore sample. S5: Repeat step S4 to obtain the proportion of gold in each gold-bearing mineral in the ore sample, and then obtain the proportions of lattice gold and microscopic gold in the ore sample, respectively, to achieve quantitative analysis of the occurrence state of gold in the ore sample.

[0006] As a further improvement of the present invention, the proportion of lattice gold in the ore sample is the sum of the proportions of gold in each gold-bearing mineral in the ore sample obtained in step S5; the proportion of microscopic gold in the ore sample is: 1 - the proportion of lattice gold.

[0007] As a further improvement of the present invention, the quantitative analysis method for the occurrence state of gold in ore deposits can quantitatively analyze the occurrence state of gold in ore samples with a gold grade of 0.1 g / t.

[0008] As a further improvement of the present invention, the pretreatment process of the ore sample is as follows: the ore sample is subjected to coarse crushing, fine crushing, sieving and reduction in sequence to obtain the pretreated ore sample; wherein, the reduction step of the ore sample follows the Chejote formula.

[0009] As a further improvement of the present invention, the types of microscopic gold include native gold, silver-gold minerals, and tellurium-gold minerals.

[0010] As a further improvement of the present invention, the particle size range of the ore sample after coarse crushing is 1~2cm; the particle size range of the ore sample after fine crushing is 2~5mm; and the particle size range of the ore sample after fine grinding is such that 80% of the finely ground ore sample can pass through a 150μm sieve.

[0011] As a further improvement of this invention, the ultra-enrichment process is as follows: first, gold in the ore sample is pre-enriched using gravity separation technology; then, the pre-enriched ore sample is washed to obtain an ultra-enriched ore sample. The ultra-enriched ore sample includes gold concentrate, sulfides, and silicates. Specifically, the number of microscopic gold particles in the gold concentrate exceeds 95% of the total number of microscopic gold particles, while the silicates do not contain microscopic gold.

[0012] As a further improvement of the present invention, in the super-enrichment process, a Nelson concentrator is used to pre-enrich the gold in the ore sample, and a super gold concentrator is used to wash the pre-enriched ore sample.

[0013] As a further improvement of the present invention, the process of making a resin target from a pretreated ore sample is as follows: the pretreated ore sample is sequentially bonded and polished to obtain the target.

[0014] As a further improvement of the present invention, the automatic quantitative analysis system for minerals adopts a dot matrix scanning mode when scanning the resin target made from the pretreated ore sample, and adopts an appearance search mode when scanning the resin target made from the super-enriched ore sample.

[0015] The technical solution provided by this invention has the following beneficial effects:

[0016] (1) The quantitative analysis method for the occurrence state of gold in ore deposits provided by this invention, through systematic separation and determination steps, combined with chemical phase analysis and microstructure characterization, can accurately identify the occurrence form and distribution characteristics of gold in ore. While improving detection accuracy and repeatability, it also realizes quantitative analysis of the occurrence state of gold. Compared with traditional qualitative or semi-quantitative methods, the quantitative analysis method provided by this scheme has higher resolution and applicability, and is suitable for the study of different types of gold deposits, providing reliable data support for subsequent optimization of beneficiation and smelting processes.

[0017] (2) The quantitative analysis method for the occurrence state of gold in ore deposits provided by this invention is based on ultra-enrichment technology and automatic quantitative analysis of minerals. Even in low-grade gold ore samples, it can efficiently and accurately find hundreds of microscopic gold particles and obtain data such as the type, color, and grain size characteristics of the microscopic gold, thus clarifying the occurrence characteristics of the microscopic gold. This data is of great guiding significance for researchers to understand the gold mineralization environment and provides reliable data support for the beneficiation and recovery of microscopic gold. Combined with the lattice gold content characteristics in sulfides obtained by LA-ICP-MS testing, the quantitative characterization of the occurrence state of gold in the ore can be achieved. This solves the problem of the inability to accurately quantitatively describe the occurrence state of gold in existing technologies, as well as the disadvantages of existing research methods being cumbersome and inefficient in the case of low-grade gold. Attached Figure Description

[0018] Figure 1 The flowchart illustrates the steps of the quantitative analysis method for the occurrence state of gold in mineral deposits provided by this invention.

[0019] Figure 2 A simplified flowchart of the steps for quantitative analysis of the occurrence state of gold in ore samples in the test examples provided by this invention.

[0020] Figure 3 The images provided in this invention are of the ore sample after being separated into gold concentrate, sulfides, and silicates through ultra-enrichment treatment, and of the gold concentrate taken under a binocular microscope. Image a is a photograph of the mineral separation obtained after ultra-enrichment of the ore sample; image b is a photograph of the first section of gold concentrate in the ultra-enriched ore sample taken under a binocular microscope.

[0021] Figure 4 The images provided in this invention are BES images of microscopic gold in the super-enriched ore sample and their corresponding reflected light images; where images a and c are BES images of microscopic gold in different regions of the super-enriched ore sample; image b is the reflected light image corresponding to image a, and image d is the reflected light image corresponding to image c.

[0022] Figure 5 The TIMA phase diagram of micro-gold in the super-enriched ore sample provided in the test example of this invention.

[0023] Figure 6 The following are LA-ICP-MS time profiles of pyrite, chalcopyrite, and bornite, and a reflectance image of a certain analysis point in the test examples provided by this invention; wherein figure a is the LA-ICP-MS time profile of bornite; figure b is the LA-ICP-MS time profile of bornite; figure c is the LA-ICP-MS time profile of pyrite; and figure d is the reflectance image of the analysis point during LA-ICP-MS analysis.

[0024] Figure 7 A quantitative representation of the occurrence state of gold in an ore sample used in the test examples provided by this invention. Detailed Implementation

[0025] The present invention will now be further described in conjunction with specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0026] In the description of this invention, it should be noted that directional terms such as "center," "lateral," "longitudinal," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limiting the specific scope of protection of this invention. The terms "first," "second," etc., in the specification and claims of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. The terms "comprising" and "having," and any variations thereof, in the specification and claims of this invention, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or devices.

[0027] This embodiment provides a method for quantitative analysis of the occurrence state of gold in mineral deposits. Please refer to [the relevant documentation]. Figure 1 It includes the following steps:

[0028] (a) Pretreatment of ore samples and gold enrichment

[0029] (1.1) Collecting ore samples: Based on geological research and observation, collect representative ore samples. The collected ore samples may be core samples, blocky hand specimens or laboratory coarse samples, etc.

[0030] (1.2) Pretreatment: The collected ore samples are coarsely crushed to a particle size of 1-2 cm, and then finely crushed to a particle size of 2-5 mm. The finely crushed ore samples are then subjected to reduction and fine grinding, ensuring that 80% of the finely ground ore samples can pass through a 150 μm sieve. The finely ground ore samples are then reduced again to obtain the pretreated ore samples. A portion of the pretreated ore samples is selected for chemical analysis to obtain the content characteristics of gold and other elements in the ore samples, while another portion is used for quantitative analysis of the occurrence state of gold. This scheme can obtain the total gold content in the pretreated samples by performing elemental major and trace analysis. In this scheme, the ratio of ore samples used for chemical analysis and for quantitative analysis of the occurrence state of gold can be 1:5.

[0031] In this step, all reduction operations must strictly follow the Chychot formula, which is as follows: q=kd 2In the formula: q is the minimum reliable mass to ensure the representativeness of the ore sample, in kg. d is the diameter of the largest particle in the ore sample, in mm, and the specific value of d can be obtained through sieve analysis. k is an empirical coefficient, which is related to the ore type, the uniformity of native gold distribution, and other characteristics. The conventional value range is between 0.02 and 0.5, and the specific value can be determined experimentally.

[0032] (1.3) Gold accumulation

[0033] The pretreated ore samples are first pre-enriched using gravity separation technology, and then washed to obtain ultra-enriched ore samples. The ultra-enriched ore samples can be divided into: gold concentrate, sulfides, and silicates.

[0034] In this step, a Nelson gravity separator can be selected to pre-enrich the pretreated ore sample, and a Superpan gold separator can be used to wash the pre-enriched ore sample. Washing the pre-enriched ore sample with a Superpan gold separator can achieve super-enrichment of micro-gold and gold sulfides. Furthermore, after separation by the Superpan gold separator, gold concentrate, sulfides, and silicates can be obtained simultaneously. The weight of the separated gold concentrate is typically 100mg~500mg, which can be used for various gold testing and analysis. The number of micro-gold particles in the gold concentrate exceeds 95% of the total number of micro-gold particles. The separated sulfides contain almost no micro-gold, and the silicates contain no micro-gold at all. (II) The pretreated ore sample and the super-enriched ore sample are analyzed using an automated mineral quantitative analysis system.

[0035] The Automated Quantitative Mineral Analysis System (TIMA) primarily comprises a scanning electron microscope (SEM) and an energy dispersive X-ray spectroscopy (EDX) spectrometer. TIMA is a fully automated quantitative analysis system for rocks and minerals based on SEM. It can simultaneously perform high-resolution backscattered electron (BSE) and energy dispersive X-ray spectroscopy (EDX) for rapid data processing and is equipped with specialized mineral processing software to assist in analyzing results and generating reports. TIMA can perform rapid quantitative mineral analysis on rocks, ores, rock fragments, concentrates, tailings, leaching residues, or smelting products. It can efficiently identify rock types, mineral species, and measure mineral content, distribution, grain size, liberation, and inclusion parameters. TIMA's quantitative analysis of mineral composition and structure reaches the micrometer scale, offering significant advantages over traditional optical microscopes and SEMs, and has been widely applied in geology, petroleum, mining, and metallurgy.

[0036] In this step, resin targets are first fabricated for the processed ore sample and the gold concentrate, sulfides, and silicates obtained after ultra-enrichment, resulting in a total of four resin targets for subsequent analysis. The fabrication process for all four resin targets is identical, and the following description uses the pre-treated ore sample as an example: the pre-treated ore sample is sequentially cemented and polished. Since this application does not improve the resin target fabrication process, it will not be described in detail. The purpose of fabricating the resin targets is to fix and protect them for precise observation and analysis of samples with small or irregular shapes. Resin, as a matrix material, can firmly encapsulate the sample, forming a flat and hard surface, thus meeting the detection requirements of various high-precision instruments. The following issues need attention in this processing step: the ultra-enriched gold concentrate has an extremely low content and is precious; therefore, careful handling is required during sample preparation to ensure that all enriched gold concentrate is prepared as much as possible.

[0037] In this scheme, TIMA can be used to scan resin targets prepared from pretreated ore samples to obtain the original mineral composition and mass fraction of each mineral, as well as the specific types and contents of gold-bearing minerals. TIMA can also be used to scan resin targets prepared from hyper-enriched ore samples to obtain data on the quantity, type, grain size distribution, and mineral co-occurrence relationships of micro-gold in the hyper-enriched ore samples. The types of micro-gold include native gold, argentite, and tellurite, among other gold minerals. A dot matrix scanning mode can be used when scanning the resin targets prepared from pretreated ore samples, while a mineral appearance search mode can be used when scanning the three resin targets prepared from hyper-enriched ore samples. It is worth noting that this application can concentrate 95% of microscopic gold particles in gold concentrate using an ultra-enrichment method. However, to avoid omissions in the statistical analysis of microscopic gold particles, this scheme uses TIMA to scan resin targets made from gold concentrate, sulfides, and silicates, ensuring the identification of all microscopic gold particles in the ore sample and improving the accuracy of the overall scheme in identifying the number of microscopic gold particles. In this scheme, with only 0.282 g / t of gold, hundreds of gold particles can be found in a single resin target, which is impossible to achieve with conventional slide preparation and observation. Moreover, more than 95% of the identified microscopic gold is distributed in the gold concentrate resin target, which proves that the ultra-enrichment treatment of this scheme can effectively ultra-enrich gold in ore samples and can greatly reduce labor and analytical testing costs. In subsequent ore deposit research, the analysis of the types and composition of microscopic gold in the gold concentrate resin target can help understand the gold mineralization environment. Furthermore, the analysis of the grain size characteristics and mineral symbiotic relationships of microscopic gold can provide a theoretical basis for gold beneficiation and recovery.

[0038] (III) Detection and analysis of gold content in sulfides using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS).

[0039] Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is an analytical instrument that combines a laser ablation system with inductively coupled plasma mass spectrometry technology. It is mainly used for in-situ determination of trace elements and isotope ratios in micro-areas.

[0040] Since gold in nature exists not only as independent minerals (such as visible gold and microscopic gold) but also often as isomorphous gold (i.e., lattice gold) in sulfides (such as pyrite, chalcopyrite, and bornite), this scheme also requires the use of LA-ICP-MS to detect and analyze the gold content in sulfides. Because the spot size of LA-ICP-MS spot analysis is generally greater than 30 μm, the sulfide particles selected for analysis must have a particle size greater than 30 μm. This is to ensure that the spot size does not affect other minerals during LA-ICP-MS spot analysis, thus improving the accuracy of the results. To ensure statistical significance, at least 10 different particles are measured for each mineral, and the average value is taken as the lattice gold content in that mineral.

[0041] In this scheme, the occurrence forms of gold in ore samples are mainly divided into microscopic gold and lattice gold. Microscopic gold refers to gold particles that can be directly observed through a microscope or scanning electron microscope; lattice gold refers to gold that cannot be directly observed as it enters the mineral lattice in an isomorphic form.

[0042] (iv) Quantitative analysis of the occurrence state of gold in ore samples based on TIMA and LA-ICP-MS analysis results.

[0043] The TIMA analysis in step (II) provides data on the mineral composition, mass fraction of each mineral, quantity, type, and particle diameter of microscopic gold in the ore sample. The LA-ICP-MS spot analysis in step (III) provides data on the gold content in each gold-bearing mineral within the sulfides. Multiplying the gold content in any gold-bearing mineral (obtained in step III) by the mass fraction of the corresponding gold-bearing mineral in the ore sample (obtained in step II) yields the gold content in that gold-bearing mineral. Dividing this gold content by the total gold content in the ore sample (obtained in step I) gives the percentage of gold in each gold-bearing mineral. Furthermore, subtracting the gold content in each gold-bearing mineral from the total gold content obtained in step (I) gives the gold content in the ore sample in microscopic form. This calculation process allows for the quantitative analysis of the gold occurrence state in the ore sample.

[0044] In this study, TIMA analysis clarified the occurrence characteristics of microscopic gold, and LA-ICP-MS testing revealed the content characteristics of lattice gold in sulfides. The combination of these two methods enables quantitative characterization of the gold occurrence states in ores. To accurately calculate the distribution ratio of gold in the two occurrence states (microscopic gold and lattice gold), in-situ LA-ICP-MS point analysis was used to obtain the average gold content of several gold-bearing minerals. This average content was then multiplied by the corresponding content of the gold-bearing minerals in the ore sample to calculate the total gold content in the ore hosted in various gold-bearing minerals. Furthermore, chemical analysis can be used to obtain the total gold content in the ore sample, which, when subtracted from the gold content in various gold-bearing minerals, allows for the calculation of the gold content in the ore sample hosted in the form of microscopic gold.

[0045] Performance testing

[0046] To verify the advantages of the quantitative analysis method for the occurrence state of gold in the deposits provided in this scheme, the Shaxi deposit in Anhui Province was used as an example for the following study.

[0047] The preparation process of the test case is as follows, please refer to... Figure 2 As shown.

[0048] (1) Collection and pretreatment of ore samples

[0049] Based on geological research and observation, representative ore samples are collected. These samples can be core samples, massive hand specimens, or coarsely crushed laboratory samples. First, the collected ore samples are coarsely crushed to 1–2 cm, then finely crushed to 2–5 mm, resulting in approximately 600 g of ore sample. This sample is then finely ground, ensuring that 80% of the ore passes through a 150 μm sieve (80%@150 μm). After further reduction, 100 g of the ore sample is used for chemical analysis to determine the content characteristics of gold and other elements. The remaining 500 g of ore sample is retained for subsequent experiments.

[0050] In this test example, a low-grade gold ore sample with a gold grade of 0.282 g / t is used as an example to quantitatively analyze the occurrence state of gold.

[0051] (2) Hyper-enrichment of ore samples

[0052] Because the gold grade in ore samples is generally low, it is difficult to observe gold minerals directly. However, gold minerals have a relatively high density among various minerals in nature, so this characteristic can be utilized for super-enrichment. The super-enrichment process is as follows: First, a Nelson gravity separator is used to pre-enrich the pre-treated ore sample. Then, a Superpan gold separator is used for further washing to achieve super-enrichment of gold minerals and gold sulfides. The super-enriched ore sample can be separated into: gold concentrate, sulfides, and silicates. It should be noted that the sample weight during the washing process using the Superpan gold separator after pre-enrichment can be 30-50g. Please refer to [reference needed]. Figure 3 As shown, Figure 3 a is a mineral separation photograph obtained after the ore sample has undergone ultra-enrichment. Figure 3 b is a photograph of the first section of gold concentrate in the super-enriched ore sample under a binocular microscope.

[0053] (3) Perform TIMA analysis on ore samples.

[0054] First, a resin target was prepared for the pretreated ore sample, and then resin targets were prepared for the ultra-enriched ore samples: gold concentrate, sulfides, and silicates, respectively. The resin targets of the pretreated ore samples were scanned using TIMA in a dot matrix scanning mode, and the data are shown in Table 1.

[0055] Table 1 shows the mineral composition and mass fraction of each mineral in the pretreated ore sample.

[0056]

[0057] Using TIMA's mineral appearance search method, resin targets made from gold concentrate, sulfides, and silicates were scanned, and the results are shown in Table 2. Table 2 presents the particle size characteristics and mass percentage of micro-gold in the hyper-enriched ore samples. Specifically, it includes the quantity, type, and particle size distribution of micro-gold, as well as the quantity and mass percentage of different particle sizes.

[0058] Table 2 shows the grain size characteristics and mass percentage of micro-gold in the ultra-enriched mineral samples.

[0059]

[0060] Analysis of Table 2 shows that a total of 149 microscopic gold particles were identified by scanning and identifying three resin targets prepared from the hyper-enriched mineral samples. These included 124 native gold particles, 16 argentite particles, and 9 tellurite particles. The maximum particle size of native gold was approximately 40 μm, while the maximum particle size of argentite and tellurite was 5 μm. It was found that over 95% of the microscopic gold particles were located within the gold concentrate resin target. The total gold content in the ore sample studied in this test case was only 0.282 g / t, but the above operation enabled the detection of over 100 microscopic gold particles in the hyper-enriched ore sample, which is impossible with conventional slide preparation and observation. This demonstrates the significant advantages of this method in the study and analysis of low-grade gold ore samples. Furthermore, in this method, TIMA (Thin-Intensity Modulation) targeting of the resin targets can quickly locate the position of microscopic gold particles in the ore sample, facilitating subsequent microscopic gold and electron probe microanalysis. Please see below. Figure 4 , Figure 4 a and Figure 4 b shows BES images of microscopic gold in different regions of the hyper-enriched ore sample. Figure 4 b is Figure 4 The image of reflected light corresponding to 'a' Figure 4 d is Figure 4 Image of reflected light corresponding to c. By observing... Figure 4 It can be seen that the symbiotic relationship of gold microscopy can be obtained quickly, such as... Figure 4 a and Figure 4 b shows native gold encapsulated in bornite; Figure 4 c and Figure 4 d shows the intergrowth of native gold and pyrite. Therefore, through Figure 4 This allows for a clear understanding of the symbiotic relationships among gold minerals, providing theoretical support for subsequent beneficiation and recovery.

[0061] When scanning a resin target using TIMA, TIMA phase diagrams of all microscopic gold in the super-enriched ore sample can be obtained, providing a direct visual representation of the morphology of the microscopic gold, such as... Figure 5 As shown.

[0062] (4) LA-ICP-MS analysis of sulfide resin targets on ultra-enriched ore samples.

[0063] Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to perform in-situ micro-area analysis on the hyper-enriched sulfide resin target. To ensure statistical significance, at least 10 different particles were measured for each gold-bearing mineral, and the average value was taken as the gold content in that mineral. Specific data are shown in Table 3. The gold-bearing minerals in the ore samples were pyrite, chalcopyrite, and bornite.

[0064] Table 3 shows the analysis of gold content in pyrite, chalcopyrite, and bornite in sulfide resin targets.

[0065]

[0066] Analysis of Table 3 reveals significant differences in gold content among different sulfides. Bornite and chalcopyrite, due to their covalently bonded structures and complex lattice features, exhibit relatively weak capacity for absorbing trace elements. For bornite, the average gold content is approximately 0.06 × 10⁻⁶. -6 For chalcopyrite, the average gold content is approximately 0.03 × 10⁻⁶. -6 Pyrite, on the other hand, is relatively more conducive to the isomorphous entry of trace elements into the mineral lattice, and its average gold content can reach 0.53 × 10⁻⁶. -6 .

[0067] Furthermore, this method utilizes LA-ICP-MS analysis of pyrite, chalcopyrite, and bornite to obtain LA-ICP-MS time profiles for pyrite, chalcopyrite, and bornite, respectively. Figure 6 As shown. Figure 6 a is the LA-ICP-MS time profile of bornite. Figure 6 b is the LA-ICP-MS time profile of chalcopyrite; Figure 6 c is the LA-ICP-MS time profile of pyrite; Figure 6 Image d shows the reflectance at a specific analysis point during LA-ICP-MS analysis. Figure 6 Analysis revealed that the gold signal curves in the LA-ICP-MS time profiles of pyrite, chalcopyrite, and bornite were generally stable without obvious pulse fluctuations. This characteristic indicates that gold mainly exists in the mineral lattice in the above sulfides in the form of isomorphous substitution.

[0068] In summary, the quantitative analysis method for gold occurrence in ore deposits provided in this scheme can clarify the occurrence characteristics of microscopic gold through TIMA analysis, and further clarify the content characteristics of lattice gold in sulfides through LA-ICP-MS testing. The combination of these two methods can achieve quantitative characterization of the occurrence state of gold in ore. Taking pyrite as an example, the TIMA quantitative analysis results show that the pyrite content in the ore sample is 0.58% (please refer to Table 1), and the LA-ICP-MS spot analysis results show that the average gold content in the pyrite of the ore sample is 0.53 × 10⁻⁶. -6 (Please refer to Table 3), multiply the two and then divide by the gold content in the ore sample obtained from chemical analysis, which is 0.282 × 10⁻⁶. -6Therefore, the proportion of gold in pyrite in the ore sample is 1.09%. Following the calculation method described above, a table of gold occurrence states in the ore sample can be obtained, as shown in Table 4; and a quantitative representation diagram of gold occurrence states in the ore sample can be obtained, as shown in Table 4. Figure 7 .

[0069] Table 4 shows the phase distribution characteristics of gold in the ore samples.

[0070]

[0071] Combine Table 4 and Figure 7 Analysis shows that, using the quantitative analysis method for gold occurrence in the ore deposit provided in this scheme, gold in the Shaxi deposit mainly occurs in the form of microscopic gold, accounting for approximately 98.78%. Of this microscopic gold, native gold is the dominant form, accounting for approximately 95.9%, followed by small amounts of silver-gold ore (approximately 4%) and tellurium-gold ore. The proportion of lattice gold in sulfides is relatively low, only 1.22%, with gold accounting for approximately 1.09% in pyrite and approximately 0.13% in bornite. Therefore, this scheme, through the combined use of multiple technologies, can quantitatively determine the occurrence state of gold in ore samples, achieving accurate differentiation and quantitative allocation of microscopic and lattice gold. This overcomes the limitations of existing technologies, which can only provide qualitative descriptions or semi-quantitative calculations, and has important indicative value for gold beneficiation and recovery. Furthermore, this scheme can still achieve efficient detection in low-grade gold ore samples, is applicable to the study of different types of gold deposits, and can significantly reduce sample preparation workload while improving analytical accuracy and repeatability.

[0072] In summary, the quantitative analysis method for gold occurrence in ore deposits provided in this scheme has higher resolution and wider applicability, making it suitable for quantitative analysis of gold occurrence in the study of different types of gold deposits. Firstly, this scheme is highly applicable to the study of gold deposits of different grades, significantly improving research efficiency and avoiding the drawback of requiring the preparation of hundreds of sections for studying low-grade gold samples. Secondly, this scheme can accurately identify gold mineral types and achieve quantitative allocation of gold occurrence states, overcoming the limitations of existing technologies that can only provide qualitative descriptions or semi-quantitative calculations, thus playing an important indicative role in gold beneficiation and recovery. Finally, this scheme can accurately identify and enrich all microscopic gold in the sample, providing high-quality samples for subsequent testing.

[0073] The basic principles, main features, and advantages of this invention have been described above. Those skilled in the art should understand that this invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made without departing from the spirit and scope of the invention, and all such changes and modifications fall within the scope of the invention as claimed. The scope of protection claimed by this invention is defined by the appended claims and their equivalents.

Claims

1. A method for quantitatively analyzing the occurrence state of gold in a deposit, characterized by, It includes: S1: Pre-treat the ore sample and obtain the total gold content in the ore sample; Gold was super-enriched in the pretreated ore samples. The process of ultra-enrichment is as follows: First, gold in the ore sample is pre-enriched using a Nelson gravity separator. Then, the pre-enriched ore sample is washed using a super gold separator to obtain an ultra-enriched ore sample. The ultra-enriched ore sample includes gold concentrate, sulfides, and silicates. Among them, the number of micro-gold particles in the gold concentrate exceeds 95% of the total number of micro-gold particles, and the silicates do not contain micro-gold. S2: Prepare resin targets for the pretreated ore sample and the ultra-enriched ore sample respectively. Use an automatic mineral quantitative analysis system to scan each resin target to obtain the mineral composition and mass fraction of gold-bearing minerals in the pretreated ore sample, as well as the quantity, type and particle size distribution of micro gold in the ultra-enriched ore sample. S3: LA-ICP-MS was used to perform in-situ micro-area analysis on the resin target of sulfides to obtain the gold content in each gold-bearing mineral contained in the sulfides. S4: Multiply the gold content in any gold-bearing mineral obtained in step S3 by the mass fraction of the corresponding gold-bearing mineral in the ore sample obtained in step S2, and then divide the product by the total gold content in the ore sample to obtain the proportion of gold in that gold-bearing mineral in the ore sample. S5: Repeat step S4 to obtain the proportion of gold in each sulfide gold-bearing mineral in the ore sample, and then obtain the proportion of lattice gold and micro gold in the ore sample, so as to realize the quantitative analysis of the occurrence state of gold in the ore sample. Wherein, the proportion of lattice gold in the ore sample is the sum of the proportions of gold in various sulfide gold-bearing minerals in the ore sample; the proportion of microscopic gold in the ore sample is: 1 - the proportion of lattice gold.

2. The method for quantitatively analyzing the occurrence state of gold in ore deposits according to claim 1, characterized by, The quantitative analysis method for the occurrence state of gold in the deposit can quantitatively analyze the occurrence state of gold in ore samples with a gold grade of 0.1 g / t.

3. The method for quantitatively analyzing the occurrence state of gold in ore deposits according to claim 1, characterized by, The pretreatment process of the ore sample is as follows: the ore sample is subjected to coarse crushing, fine crushing, fine grinding, sieving and reduction in sequence to obtain the pretreated ore sample; wherein, the reduction step of the ore sample follows the Chejote formula.

4. The method for quantitatively analyzing the occurrence state of gold in ore deposits according to claim 3, characterized by, Microscopic gold includes native gold, silver-gold deposits, and tellurium-gold deposits.

5. The method for quantitatively analyzing the occurrence state of gold in ore deposits according to claim 1, characterized by, The particle size range of the ore sample after coarse crushing is 1~2cm; the particle size range of the ore sample after fine crushing is 2~5mm; the particle size range of the ore sample after fine grinding is such that 80% of the finely ground ore sample can pass through a 150μm sieve.

6. The method for quantitatively analyzing the occurrence state of gold in ore deposits according to claim 1, characterized by, The process of making resin targets from pretreated ore samples is as follows: the pretreated ore samples are sequentially cemented and polished to obtain the resin targets.

7. The method for quantitatively analyzing the occurrence state of gold in ore deposits according to claim 1, characterized by, The automated quantitative mineral analysis system uses a dot matrix scanning mode when scanning resin targets made from pretreated ore samples, and an appearance search mode when scanning resin targets made from ultra-enriched ore samples.

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