sidrunit

Sidrunit is a rare mineral discovered in 2019, found in the Kola Peninsula of Russia. It is a new member of the niobate mineral group, which includes minerals that contain niobium (Nb) and oxygen (O) in their crystal structure. Sidrunit has the chemical formula (K,REE)2(Nb,Ta)2O6(OH,F)2, where REE stands for rare earth elements. The mineral is named after the Russian word "sidr," meaning "sapphire," reflecting its blue color and the presence of rare earth elements.

Sidrunit crystallizes in the monoclinic system and typically forms prismatic crystals. Its color ranges from blue to blue-green, with a vitreous luster. The mineral has a Mohs hardness of 5.5 to 6 and a specific gravity of approximately 4.5. Sidrunit is often found in association with other niobate minerals such as columbite and tantalite, as well as with rare earth element-bearing minerals.

The discovery of sidrunit has contributed to the understanding of the complex mineralogy of the Kola Peninsula and has provided insights into the geological processes that led to the formation of these rare minerals. Further research on sidrunit and its crystal structure may lead to the discovery of new minerals and a better understanding of the geological history of the region.