Market Analysis and Applications of Vein Quartz
Vein quartz is not a mineralogical name but refers to rock almost entirely composed of quartz, formed by hydrothermal or metamorphic processes, and occurring in vein form. The quartz content can exceed 99%, with minor inclusions of pyrite, specularite, hematite, chalcopyrite, galena, feldspar, and mica. The rock is typically white or light gray with a greasy luster, anhedral texture, and is hard and dense.
Formation and Characteristics
Vein quartz mainly occurs in granite or metamorphic regions associated with migmatization. The ore bodies appear in vein or lens shapes, ranging from a few meters to tens of meters in thickness, and can be hundreds of meters long. These deposits are usually small-scale, often as single or multiple veins. Due to its high SiO2 content, generally over 99%, vein quartz is relatively easy to process into high-purity quartz sand with SiO2 content exceeding 99.9%.
Physical and Chemical Properties
As a raw material for high-purity quartz, vein quartz possesses unique physical and chemical properties. Its intrinsic crystal structure, shape, and lattice changes confer high-temperature resistance, low thermal expansion, high insulation, corrosion resistance, wear resistance, piezoelectric effect, resonance effect, and unique optical properties.
Vein Quartz Resources in China
China's vein quartz resources include those for glass, cement blending, and metallurgy. According to research by Jiao Lixiang from the Shandong General Team of the China Building Materials Industry Geological Survey Center, by the end of 2017, identified resources for glass-grade vein quartz amounted to 92.04 million tons, with 20.39 million tons as basic reserves and 71.65 million tons as resources. However, the proportion of these resources suitable for producing high-purity quartz is very low. Major deposits are found in metamorphic regions of Jiangxi, Sichuan, Anhui, Xinjiang, Heilongjiang, Shaanxi, and Zhejiang.
Distribution and Exploration
Glass-grade vein quartz is primarily found in small to medium-sized deposits, with only one large deposit, 12 medium-sized, and 184 small-sized deposits. Small to medium deposits account for 99.49% of the total, holding 84.52% of the resources. Between 2008 and 2017, the reserves of glass-grade vein quartz showed an overall growth trend. Notable high-grade deposits include Lingqiu Mountain in Qichun County, Hubei Province (SiO2 content 99.35%), Donghai County, Jiangsu Province (SiO2 content 99.19%), and Longchuan in Banshu Township, Jingde County, Anhui Province (SiO2 content 99.01%).
Exploitation and Utilization
As of 2017, China's glass-grade vein quartz mines had varying degrees of exploration: 42% in detailed exploration, 15% in reconnaissance, and 42% in general surveys. Nearly half of the glass-grade vein quartz mines are very small, with very few large deposits. There are 19 deposits with over one million tons, but only one is large-scale. The development and utilization of these mines are relatively low, with only 95 out of 195 being actively mined. The rest are either planned for near-term use, recommended for near-term use, suspended, or in reserve.
Application Market Overview
Vein quartz in China is primarily processed into high-purity quartz sand, which is a key raw material for quartz glass and crucibles. Its downstream applications are mainly in three areas: lighting, photovoltaics, and semiconductor and optical fiber manufacturing. Despite the late development of China's semiconductor industry, domestic production covers only about 10% of demand, with 90% of chips being imported and self-sufficiency in semiconductor equipment being less than 5%, leading to a very low rate of domestically produced quartz materials.
Market Demand and Future Prospects
According to a prospectus by Quartz Co., Ltd., the domestic quartz glass market was valued at 5.316 billion yuan in 2012. The demand structure included 23% for integrated circuits and discrete components (including LED GaAs and front-end photovoltaic devices), 7.5% for optical fibers and military use, 35% for silicon single crystal quartz crucibles (mainly photovoltaics), 21% for lighting, and 14.5% for other products.
Overall, due to the concentration of domestic quartz product demand in mid- to low-end fields such as lighting and photovoltaics, the localization of semiconductor quartz materials has great potential. With the rapid development of China’s specialty glass and information technology industries, the annual growth rate for high-purity quartz raw materials is approximately 20%. CSGore color sorter provides strong support for high-end ore processing. As a crucial raw material for high-end quartz products, the demand for vein quartz will increase.
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