Quartz (SiO2) is, next to feldspar, the commonest mineral. It is an important rock-forming mineral, being one of the main components of the majority of granites and other igneous rocks. Under conditions favorable for crystallization, such as voids in rock, it forms sharp-pointed hexagonal long and slender crystals which are widely used as a popular ornamental stone and also a gemstone in jewellery. Depending on admixture of coloring oxides, several varieties of these gemstones are differentiated: clear and colorless rock crystal, yellow to orange citrine, pink to rose red rose and pink quartz, purple to violet amethyst, brown to gray smoky quartz and black morion.
Quartz also forms veins and lenses in metamorphic and igneous rocks. Quartz vein deposits originate in result of hydrothermal activity as an infill of open fissures and fractures cutting a given rock massif. The quartz infills are characterized by high content of silica (SiO2) and low content of coloring oxides (Fe2O3 and TiO2).
In Poland quartz veins occur mainly in crystalline rock massifs of the Precambrian and Paleozoic in the Sudety Mts (map). The deposits are characterized by a high variability in thickness and quality of raw material as well as in generally high dip of veins and lenses.
Vein quartz is widely used in the industry, starting from ceramic industry (production and glazing and decorating bone and fine china, porcelain and porcelite, utility and pottery ware ceramics, technical ceramics) to production of fire-proof materials and in metallurgy. Its purest varieties are used in manufacturing high-quality glass and in chemical and electrotechnical industries. Quartz vein is also the source of high-quality quartz powder and fine grade crushed grains.
The table 1 given below shows resources and the current state of exploration and development of deposits of vein quartz.
The largest economic resources hitherto discovered are 3.3 million tonnes in the Stanisław deposit situated south-west of Jelenia Góra and 1.5 million tonnes in the Krasków deposit from the vicinities of Świdnica, Sudety Mts. There are chances for discovery of some new deposits as potential resources in that region are estimated at about 4 million tonnes. It should be added that the known minor deposits were found to be characterized by very good quality of quartz raw material.
Three deposits are developed: Krasków, Stanisław and Taczalin. In the year 2010, any of these deposits has not been exploited.
In 2010, import of quartz increased by 15 % in comparison with the previous year. It was equal 8.33 thousand tonnes with Norway as the major supplier (72 %). Export was negligible, amounted to 114 tonnes.
- B - for solid minerals - mine in building process, for fuels - prepared for exploitation or trial period of the exploitation
- E - exploited
- G - underground natural gas storage facilities
- M - deposit crossed out of the annual report of mineral resources during analized period
- P - deposit covered by preliminary exploration (in C2+D category, for fuels – in C category)
- R - deposit covered by detailed exploration (in A+B+C1 category, for fuels – in A+B category)
- Z - abandoned deposit
- T - deposit exploited temporarily
- K - change of the raw material in deposit
Prepared by: Agnieszka Malon