The brine deposit located in Zabłocie in the Strumień commune has been exploited since it was opened with the Korona borehole in 1892. The brine was used from the turn of the 19th and 20th centuries for therapeutic (bathing and inhalation) purposes, initially under the name "Zablaczer Kronenjodwasser".
The mining plant captures the relict waters of the warm Miocene sea, lying at a great depth: 300 - 650 m below sea level, constituting a kind of preserved algae extract and currently a deposit of healing water - iodide, chloride-sodium, rich in minerals necessary for health - iodine, calcium, magnesium and iron as well as valuable micronutrients: silicon, strontium and boron. It is typical groundwater of deep geological levels, isolated from the surface. The water has a therapeutic, very high content of iodine - 135 mg / l on average, 139 mg / l and iron approx. 10 mg / l.
Brine from the "Korona" drillhole in Zabłocie is used as a raw material for cosmetics and balneological products.