Sklopísek Střeleč, joint stock company produces high quality glass, foundry, technical, filtration and sport sands, fine milled silica flour and siliceous clays. The Střeleč area represents the largest deposit of prime quality glass sand within the Czech Republic. The sands have been extracted and processed since 1939. The quarry is located 12 kilometres to the northwest of Jičín, at the communities of Střeleč, Mladějov and Újezd pod Troskami. The deposit originated by sediments settling into a relatively shallow, well-aerated sea of the Mesozoic, Cretaceous formation. The deposit is created by sandstones cemented by kaolin with content of SiO2 above 98,5 %. The dominant fraction in granularity is 0,10 up to 0,63 mm. The quality of sand is positively affected by very low content of colouring oxides Fe2O3, TiO2, Al2O3. The deposit is being extracted by the open-cast mining in the quarry. Natural high purity sands from Sklopisek Střeleč are basic raw materials for production of crystal, container and flat glass and glass fibres. The sands are also suitable for wide sphere of use in the foundry and automobile industries, as well as for production of glaze and enamels. The chemical purity and favourable particle size distribution of the sand is appreciated in other industrial sectors such as the electrical, rubber, construction industries, in water treatment and in the building industry.
Bureau Veritas Quality International awarded Sklopísek Střeleč certificate ISO 9001 in 1998 and certificates ISO 14001 and OHSAS 18001 in 2003.