Native sulfur deposits occur in the vicinities of Tarnobrzeg (Osiek, Baranów, Machów and Jeziórko deposits), Staszów (Solec and Grzybów deposits) and Lubaczów (Basznia deposit) in the northern part of the Carpathian Foredeep (map).
Sulfur occurring in the area mentioned above is in the form of fillings of fissures and small cavities in Tertiary (Miocene-Torton) rocks, mainly post-gypsum limestones. Its origin was connected with a reduction of a calcium sulfate (gypsum) by microorganisms in a presence of hydrocarbons. The content of sulfur in these rocks may reach up to 70% at the most, ranging from 25% to 30% at the average.
Poland was one of the world's largest producers of sulfur till the 1980s. However, the growth in the recovery of sulfur from sour natural gas and crude oil caused a significant decrease in importance and value of native sulfur deposits.
The production of native sulfur is at present limited to Osiek deposit where sulfur is mined from the surface using the Frasch hot water method. The Osiek mine remains the last large native sulfur mine in the world. Outside Poland small amounts of native sulfur are produced from deposits of a volcanic origin. There are four sour gas and oil fields in Poland. Their total resources of sulfur were estimated at 571 thousand tonnes. Sulfur is recovered from sour gas and oil in Zielin, BMB (Barnówko – Mostno – Buszewo), Cychry and (from time to time) Górzyca fields.
The recovery of sulfuric acid in processing of copper and zinc and lead ores is of limited economic importance, being conducted mainly for protection of the natural environment. The production of sulfuric acid on the basis of pyrites was given up several decades ago.
Table 1 shows resources and the current state of exploration and development of sulfur deposits.
When documenting sulfur deposits the limit values of the parameters that define the anticipated economic resources are: the minimum sulfur content in the sample contouring the deposit of 10%, the minimum average sulfur content in deposits bed of 10%, the minimum deposit richness of 75m% and the maximum depth of deposit base of 400 m.
Anticipated economic resources amounted to 504.6 million tonnes in 2016. The production of sulfur in 2016 amounted to 645 thousand tonnes(table 2). This volume includes 620.5 thousand tonnes of sulfur from Osiek deposit and 24.5 thousand tonnes of sulfur which was a by-product of desulfurization of sour natural gas.
The figure given below shows changes in domestic resources and production of sulfur in Poland in the years 1989-2016.
Prepared by: Robert Bońda