Core Viewpoint - The article discusses the characteristics, distribution, and mining potential of vein quartz resources in China, highlighting the geological features, types of deposits, and regional resource distribution. Group 1: Resource Overview - China has identified a total of 608 vein quartz mining sites with an estimated resource volume of approximately 4.1 billion tons, primarily used for glass and metallurgy, with some regions utilizing it as a silica component in cement [2][3]. - The vein quartz deposits are characterized by small to medium-sized mining sites, with a concentration in regions such as Jiangxi, Fujian, and Xinjiang, while Qinghai and Jiangxi have the highest resource volumes [11][12]. Group 2: Geological Features - The formation of vein quartz deposits spans from the Archean to the Cenozoic eras, primarily influenced by tectonic and magmatic activities, with fractures and structural slip surfaces being the main locations for mineralization [5][9]. - The types of vein quartz deposits include magmatic hydrothermal and metamorphic hydrothermal types, with the former being predominant [9]. Group 3: Mining Districts and Characteristics - The article categorizes various mining districts based on geological and mineralization characteristics, detailing specific deposits and their silica content [15][16]. - Notable mining districts include the Altai region, with a silica content of 97.5% and a confirmed resource volume of 427.3 million tons, and the Ili microplate, with silica content ranging from 96.17% to 98.19% and a resource volume of 283.98 million tons [19]. Group 4: Regional Distribution - The distribution of vein quartz resources varies significantly across different provinces, with Jiangxi having the highest resource volume of approximately 4735.46 million tons, followed by Fujian and Xinjiang [13][14]. - The article provides a detailed map of resource distribution, indicating that the majority of mining sites are small to medium-sized, with a total of 176 small, 77 medium, and 19 large deposits identified [11][13].

Group 1 - The significance of high-purity quartz lies in its applications across various industries such as semiconductors, high-temperature lamps, telecommunications, optics, solar silicon, and microelectronics, with a quality standard set at SiO2 ≥ 99.9 wt.% [1][3] - The rapid development of markets in semiconductors, optical communications, and photovoltaics has led to a relative scarcity of high-purity quartz resources, prompting evaluations of quartz raw materials for economic value and efficient resource utilization [3][4] - Hydrothermal quartz, characterized by large crystal grain sizes and high SiO2 content, is identified as an ideal raw material for high-purity quartz processing, potentially replacing natural crystals [3][4] Group 2 - The four quartz samples from Laos, Zimbabwe, South Africa, and Pakistan exhibit varying degrees of transparency and are all coarse-grained with an oily luster, lacking visible accompanying minerals [2][3] - The presence and type of inclusions in quartz crystals significantly affect the quality of high-purity quartz sand, with fine mineral inclusions making processing more challenging [4][5] - The samples from Laos and Zimbabwe show minimal inclusions, while those from South Africa and Pakistan have more developed inclusions, although some grains remain clean [5][6] Group 3 - Purification experiments on the four quartz samples involved multiple processes, resulting in quartz sands with SiO2 content reaching approximately 99.99 wt.%, with specific impurity levels detailed in a table [6][7] - The purified quartz sands primarily contain impurities such as Li, Al, Ca, and Ti, with the highest SiO2 content recorded at 99.992 wt.% for the Laos sample and the lowest at 99.989 wt.% for the Zimbabwe sample [7][8] Group 4 - Microscopic observations of the purified quartz sands reveal fewer inclusions, indicating a higher purity level, although some samples still retain certain inclusions that may contribute to impurity elements [8][10] - The main components of the fluid inclusions in the quartz samples are CO2 and H2O, which are easier to remove during processing, leading to a cleaner final product [11]

Core Viewpoint - China's quartz resources are abundant, primarily consisting of quartzite, quartz sandstone, and vein quartz, but the proportion of high-purity quartz products is very low, leading to a heavy reliance on imports for high-purity quartz sand production [1] Group 1: Quartz Resource Characteristics - The main sources of high-purity quartz raw materials are crystal, vein quartz, and granite-type quartz, with granite-type quartz emerging as a new direction for high-purity quartz resource exploration due to its large scale, low impurities, and stable quality [1] - Research in the Altai region of Xinjiang has focused on granite-type quartz, revealing that the quartz veins are located within the Cambrian Kanas rock group, with a mineral composition that includes quartz, potassium feldspar, plagioclase, and biotite [3] Group 2: Purification Techniques - The purification process for granite-type quartz involves a combination of physical and chemical methods, including grinding, heavy separation, magnetic separation, and flotation, achieving high efficiency in separating quartz from other minerals [12] - After deep chemical purification, the total impurity content of quartz samples was reduced to 23.35 μg/g, indicating the potential for producing high-end high-purity quartz products with SiO2 content reaching 99.9983% [14] Group 3: Regional Exploration and Potential - The Luoyang Longquanping granite-type quartz deposit in Henan has been analyzed, showing a mineral composition similar to that of the Spruce Pine deposit in the U.S., with potential for high-purity quartz production [6] - The East Qinling-Dabie orogenic belt in Henan has revealed nearly 7,000 granite-type quartz veins, indicating significant exploration potential for high-purity quartz industrial deposits [7]