Quarried natural resources
Quarried natural resources comprise a great number of mineral deposits, in particular gravel and sands, broken natural stone, lime, marl and dolomite stones, gypsum and anhydrite stones, as well as clays and loams. Quarried natural resources are bulk raw materials; due to geological conditions, they are site-bound and not distributed evenly across the country.
Quarrying has been handed down since the beginning of human history. According to scientific findings, the oldest known “stones from human hands’ originate from the 9th to the 8th century B.C., taken from ground fortifications in the Middle East. The extraction of quarried natural resources also has a very long tradition in Germany. In the past, these raw materials were mainly extracted by hand, but companies today use modern technology. Geophysics, GPS, intelligent machine and plant control and largely automated processes control the extraction of these natural resources.
Every year, the building materials and quarrying industry extracts approx. 560 million tonnes of primary raw materials or uses these materials in production. In 2018, gravel and sands, with around 259 million tonnes, and broken natural stone with some 226 million tonnes were among the most important raw materials in the German extractive industry. In 2018, the gravel, sand and natural stone extraction sector in Germany employed 38,02651 people and operated around 2,700 extraction sites.
Industrial minerals are mineral rocks that can be immediately used in industry due to their special chemical and physical properties, i.e. without any substance conversion. In addition to the salts already mentioned, this group includes kaolin (also called china clay or porcelain earth), quartz sand, quartzite, feldspar, sticky sand, bentonite, special clay, silicas, fluorite and barite.
Industrial minerals have been extracted in Germany for hundreds of years in very diverse quantities. Apart from salts, the two most important industrial minerals in Germany in terms of volume are quartz sand/ gravel and clay (for coarse and fine ceramics) with production volumes of around 10.7 million tonnes, approx. 3.1 million tonnes (clay for fine ceramics), and 11.3 million tonnes (clay for coarse ceramics) in 2018.
The extraction of industrial minerals in Germany is extremely regional in structure, due to natural conditions. While, for example, kaolin is mainly extracted in Bavaria and Saxony and silica in Bavaria, respectively, the extraction of special clay is mainly concentrated in Rhineland-Palatinate and Hesse.
Due to their chemical and physical properties, industrial minerals are mainly used in the paper, chemical, glass, ceramic, refractory, foundry and steel industries. However, the pharmaceutical industry, environmental management (exhaust gas purification, wastewater treatment plants, solar panel and wind turbine plants) and the automotive industry also use industrial minerals.
In Germany, iron ore is mined in North Rhine-Westphalia and Saxony-Anhalt. The iron ore extracted here is not smelted into iron, however; it is used mostly in the form of crushed stone, chippings and brittle sands as a coloured and iron-rich aggregate for the concrete or cement industry.