Refractory quartzites

Quartzite is a compact hard metamorphic rock which was originally sandstone. Pure quartzite is a recrystallized sandstone with siliceous cement, often over 99 % SiO₂ and almost exclusively built of quartz grains cemented with silica. In the insulating material industry, that name of fire-proof quartzite is used for both pure quartzite and other silica-rich rocks such as quartzitic sandstones and schists.

Refractory quartzites are used in metallurgy for making ferroalloys and in insulating material industry for making siliceous fire-proof materials.

In Poland, quartzite deposits occur in two regions: the Lower Silesian region and the Holy Cross Mts (map). In the Lower Silesia, proven deposits occur in area between Bolesławiec, Lubań and Lwówek Śląski and in the vicinities of Strzelin. They are formed of irregular quartzitic layers and lenses dated at the Tertiary. The majority of these sites were exploited in the past so the abandoned deposits still comprise some relict resources. It should be added here that two quartzite deposits from Milików still have to be developed.

Quartzite deposits occurring in the Holy Cross Mts are formed by quartzite intercalations in clays and clay shales of the Paleozoic age. The deposits were explored in the 1950s but only one of them (the Bukowa Góra) is still being exploited. The raw material of that deposit has not been classified as fire-proof quartzite but quartzitic sandstone. Therefore, the Bukowa Góra deposit is discussed in the section on dimension and crushed stones. The raw material from that deposits is exploited and processed for use in producing fire-proof quartzite materials.

The table 1 given below 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 was at the same level as in the previous year and was equal 6.88 million tonnes.

The figure given below shows resources and production of refractory quartzites in Poland in the years 1989-2011.

Table 2. List of quartzites deposits - thousand tonnes

Prepared by: Agnieszka Malon