Phoscorite

Phoscorite is a rare igneous rock composed primarily of the mineral kirwanite, a calcium-magnesium-iron phosphate, along with magnetite and olivine. It is a relatively new discovery in the field of geology, with its formal description and classification occurring in the early 21st century. The rock is typically found in association with carbonatite intrusions, suggesting a common mantle origin.

The characteristic dark color of phoscorite is due to the presence of magnetite. Kirwanite, the defining mineral, often appears as a greenish to brownish crystalline phase. Olivine, a common silicate mineral, contributes to the overall mineralogy. The texture of phoscorite can vary but is generally coarse-grained.

Phoscorite is of scientific interest due to its unusual mineralogical composition and its association with carbonatites, which are themselves rare and hold significance for understanding mantle processes and the formation of certain mineral deposits. Research on phoscorite aims to shed light on the petrogenesis of these rocks and their role in the Earth's crust. While not a commercially significant rock in itself, its occurrence can be an indicator of underlying geological activity and potential mineral resources. Its rarity means that occurrences are localized and subjects of ongoing geological study.