fosfatstein

Fosfaatsteen (phosphate rock) is a sedimentary rock with a high content of phosphate minerals, principally apatite. It occurs as nodules or beds in marine sedimentary rocks such as limestone and shale, and also in guano-derived deposits. The dominant phosphate minerals are fluorapatite and hydroxyapatite, with minor minerals and trace elements.

Formation is linked to ancient marine environments with high biological productivity. Organic material from shelled organisms and fecal pellets leads to calcium phosphate precipitation during diagenesis, concentrating phosphate into economic deposits through sedimentation and compaction.

Globally, production is concentrated in a few regions. The largest share comes from Morocco and Western Sahara, followed by China, the United States (notably Florida), and Tunisia and Algeria. Deposits are typically stratiform or bedded phosphorites associated with sedimentary sequences dating from the Cretaceous to Miocene.

Uses are centered on agriculture. Fosfaatsteen is mined and processed into phosphorus-containing fertilizers, such as superphosphate and ammonium phosphate, and can be further converted into phosphoric acid and various phosphate derivatives for agricultural, feed, and industrial applications.

Economics and environment: Phosphate mining is of major economic importance but carries environmental concerns, including habitat disturbance, dust, and potential contaminants in some deposits. The geographic concentration of supply can affect prices and security of global phosphorus resources, prompting discussions on recycling, alternative sources, and sustainable mining practices.