The term phosphate rock or Phosphorite is widely used to refer any rock with high phosphorus content.
Estonian phosphorite rock (
5-20% P content ) is a brownish-grey
Obolus sandstone containing Lingula valves and detritus. Given sedimentary ore also contains substantial amount of rare earth elements (REEs - elements from lanthanum to lutetium). As the world-wide demand for heavy REEs (HREEs) for high-tech industries is growing exponentially, the interest towards possibilities to use Estonian phosphorite is rising.