Mineral resources of Poland> Rock raw materials and others> Refractory quartzites
Refractory quartzites
Quartzite is a compact hard metamorphic rock consisted mainly of the quartz grains. The silica (SiO2) content is over 99%. It is the so-called pure quartzite – recrystallized sandstone with a siliceous cement. In the refractory materials industry the name of refractory quartzites is used both for pure quartzites and other rocks which are silica-rich e.g. quartzitic sandstones and quartzitic schists.
In Poland, refractory quartzites deposits have been documented in two regions: the Lower Silesian region and the Holy Cross Mts. (map). Most of the geological elaborations (geological documentations, registration cards) were performed in 1950s, 1960s and 1970s of the last century.
In the Lower Silesia, quartzites occur in the form of irregular layers and lenses dated at the Neogene. The majority of these sites were exploited in the past. After the exploitation stopped some relict resources remained and deposits were classified as abandoned. Nowadays, only Milików deposit located in Dolnośląskie Voivodeship remained as covered by the detailed exploration but has not been exploited so far.
Quartzites deposits occurring in the Holy Cross Mts. are formed by quartzite intercalations in clays and clay schists of the Paleozoic age. These deposits were documented in 1950s but only one of them (Bukowa Góra deposit in Łączna near Zagnańsk) is still being exploited. The raw material of that deposit has been reclassified from refractory quartzite to quartzitic sandstone. Therefore, Bukowa Góra deposit is discussed in the chapter on Dimension and crushed stones. Nevertheless, the raw material from that deposit is exploited and processed for use in producing of industrial quartzite.
In the past, refractory quartzites were the important raw material used in the metallurgy for the production of ferroalloys and in a refractory materials industry for the production of siliceous refractory materials. Nowadays, none of refractory quartzites deposits is being exploited.
The Table 1 shows resources and the current state of development and exploration of refractory quartzites.
Table 1. Quartzites - million tonnes
Anticipated economic resources of the refractory quartzites amounted to 6.59 million tonnes in 2018 and have not changed in comparison with the previous year (Table 2).
The figure given below shows resources and production of refractory quartzites in Poland in the years 1989-2018.
Table 2. List of quartzites deposits - thousand tonnes
Prepared by: Agnieszka Malon