Phosphorites are mainly used by an agriculture industry (the production of phosphate fertilizers). They are also used, but with a much less importance, in a chemical industry as a raw material for the production of various phosphorus compounds.
In Poland phosphorites occur in the form of calcium phosphate-rich nodules in the various types of sediments in the belt of the Albian (Lower Cretaceous) outcrops at the north-eastern margin of the Holy Cross Mts. (vicinities of Radom-Iłża-Annopol-Gościeradów-Modliborzyce). They are used for the production of phosphate fertilizers) The exploitation of phosphorites started in Poland between the First and the Second World War. However, nowadays any of deposit is being under exploitation due to the economical reasons. The Chałupki mine was closed in 1961 and the Annopol mine in 1971.
The actual Polish limit values of the parameters that defines the phosphorites deposit establish that: the maximum depth of deposits documentation is 400 meters below the surface, the minimum P2O5 content in calcium phosphate-rich nodules is 15% and the minimum affluence of calcium phosphate-rich nodules is 1,800 kg/m2. Qualitative parameters of the main phosphorites occurrences are presented in Table 1.
At present, all Polish phosphorites deposits are abandoned as their limiting parameters are markedly below cut-off grade for the economic exploitation. Deposits are flooded and their significant parts were built-up or covered by roads, railways and high-voltage lines. It may sometimes cause the resources reduction by 50-80%. These were the reasons why in 2006 the deposits have been crossed out from "The balance..." and a demand is fully covered by import.
Prepared by: Robert Bońda