General information and occurrence
Magnesite (magnesium carbonate - MgCO3) originates from a decay of magnesium-rich igneous rocks under hydrothermal conditions and forms white accumulations.
Polish magnesite deposits are related to the Sobótka, Szklary, Grochowa-Braszowice massifs of Precambrian serpentinites and the Gogołów-Jordanów massif of ultramafic rocks in the Lower Silesian region (map). Up to the present, six magnesite deposits have been documented in this region. The deposits are of the vein type, with individual veins attaining up to 3 m in thickness and characterized by a complex geological structure and a high variability in the raw material quality. Magnesite is currently exploited in an open strip mine at Braszowice only.
Magnesite is used mainly as a semi-manufactured material in the production of multi-component artificial fertilizers, in the purification of potable water and sewage treatment and as a mineral additive to animal feed.
Resources and output
Table 1 shows resources and the state of development and exploration of magnesite deposits in Poland.
Anticipated economic resources of magnesites as of the end of 2021 decreased in comparison with the previous year due to the exploitation by 101.94 thousand tonnes and amounted to 13,399.57 thousand tonnes.
In 2021, the domestic output of magnesites (from the only deposit under exploitation - Braszowice) was equal only 65.82 thousand tonnes and increased by 0.57 thousand tonnes (0.87%) in comparison with 2020. In the years 2011-2019, the exploitation remained within a range of 75-102 thousand tonnes, so the last two years with the exploitation level of about 60 thousand tonnes indicated the significant drop.
The figure given below shows changes in resources and output of magnesites in Poland in the years 1989-2021.
Prospective resources, within three serpentine massives: Gogołów-Jordanów, Szklary and Groszowa-Braszowice, are assessed to be equal 3.25 million tonnes*.
Prepared by: Agnieszka Malon
* Sroga C., 2020 - "Magnezyty (magnesite)". W: "Bilans perspektywicznych zasobów kopalin Polski wg stanu na 31.12.2018 r." (red. Szamałek K., Szuflicki M., Mizerski W.): 350-352. PIG-PIB, Warszawa [in Polish].