In addition to the mineral natural resources described in the following section (vii. Other natural resources), salts are industrial minerals. Industrial minerals are mineral resources that can be immediately used in industry due to their special chemical and physical properties, i.e. without any substance conversion. A distinction is made between rock salt, potash salts and magnesium salts.
Germany has large salt deposits, which are mainly concentrated in northern Germany. Over millions of years, deposits of salts resulted in several 100 m-thick layers. Bavarian and Austrian Alps salt is of a similar age and has been extracted for thousands of years. The commissioning of the world’s first potash factory in Staßfurt in 1862 marked the beginning of what is now a 150-year tradition of German potash mining.
The extraction of salt by solubilisation, i.e. by making it soluble using water injected via boreholes, or by mining in salt mines, has a long history. People were digging for salt in the Berchtesgaden area as early as the 12th century. In the 16th century a salt mine was built there which is still in operation today.
In 2021, the amount produced in Germany was approximately 16.7 million tonnes of rock salt (including industrial brine) and some 6.4 million tonnes of potash and potash salt products. This is roughly equivalent to a value of €2.5 billion and it accounts for a 0.6% share of GDP. Salts accounted for around 19% of the total value of natural resources mined in Germany in 2021. This means that salts ranked 2nd among all natural resources mined in Germany in terms of economic importance. Domestic production covered 100% of German requirements for salts (2021). With a total production of approx. 5%, Germany was the fourth largest producer of salt in the world in 2021, after China, the USA and India, and also the fifth largest potash producer with around 5% of the world’s total production. In 2021 and 2022, a total of 7,825 and 8,198 persons were directly employed in potash mining in Germany and a further 2,366 and 2,386 were employed in salt mining.1
Extraction takes place in Germany in five potash mines (in Hesse, and Thuringia), seven salt mines (in Baden-Wuerttemberg, Bavaria, Lower Saxony, North Rhine-Westphalia, Saxony-Anhalt and Thuringia), six salt works (in Baden-Wuerttemberg, Bavaria, Lower Saxony and North Rhine-Westphalia, and Saxony-Anhalt) and ten solubilisation facilities (in North Rhine-Westphalia, Schleswig-Holstein, Lower Saxony, Saxony-Anhalt and Thuringia), including one operation for the extraction of potash salts (Thuringia).2
Salt and potash mining is carried out in the mines by means of drilling, blasting or cutting techniques or by brining out underground deposits (solubilisation). Brining out is done by introducing freshwater or half-brine into the salt deposits through borehole probes, after which the salts dissolve. The brine is then pumped through a probe and processed above ground in salt works or specialized facilities, where it eventually becomes salt, potash salt and other products.
Rock salt and evaporated salt is used for commercial and industrial purposes as well as for food and de-icing. Salt is an indispensable natural resource for the chemical industry, e.g. in the production of soda, chlorine and caustic soda. Glass, plastic and aluminium could not be produced without salt. It is used as regenerating salt in water softening plants, in the feed industry, in road services, for snow clearing and in the food industry. Sodium chloride meets particularly high purity requirements as an active pharmaceutical ingredient.
Potash crude salts are largely mined but, to a lesser extent, they are also extracted using other methods. The salts are mainly used in agriculture as fertilisers. However, they are also used as industrial salts in electrolysis and other industrial processes – and there is a demand for these salts in highly-purified form for the food and feed industries and for pharmaceutical purposes.