Phosphoriamidilla

Phosphoriamidilla is a rare and unusual mineral that was first discovered in 1994 in the Khibiny Mountains of Kola Peninsula, Russia. It is a member of the apatite group, which includes minerals that share a similar crystal structure and chemical composition. Phosphoriamidilla is characterized by its unique chemical formula, (NH4)2Ca(PO4)F, which includes ammonium (NH4) and calcium (Ca) ions in its structure. This composition is distinct from other apatite minerals, which typically contain sodium or potassium ions instead of ammonium.

The mineral is typically found in association with other phosphate minerals such as fluorapatite and vivianite. It forms as a secondary mineral in the oxidation zone of phosphate-bearing rocks, often in the presence of ammonium-rich fluids. Phosphoriamidilla crystals are small and usually occur as aggregates or coatings on other minerals. The mineral is translucent to transparent and has a white to pale yellow color. Its hardness on the Mohs scale is approximately 4.5, and it has a specific gravity of around 2.9.

Phosphoriamidilla is of limited interest to mineral collectors due to its rarity and small crystal size. However, it is significant to geologists and mineralogists as it provides insights into the geochemical processes that occur in the oxidation zone of phosphate deposits. The discovery of phosphoriamidilla has contributed to the understanding of the complex interactions between minerals and fluids in these environments.