natrosilite

Natrosilite is a rare mineral with the chemical formula Na2Si2O5. It is a silicate mineral belonging to the pyroxene group, although its structure is more complex than typical pyroxenes. Natrosilite is characterized by its pale yellow to colorless appearance and a vitreous luster. It typically forms in veins and cavities within igneous rocks, particularly those rich in sodium and silica. Its formation is thought to occur under moderate temperatures and pressures. The mineral is named after its chemical composition, sodium (natro-) and silicate (silite).

The crystal system of natrosilite is monoclinic, and it commonly occurs as prismatic crystals or as granular aggregates. Hardness on the Mohs scale is typically around 5.5 to 6, making it moderately hard. Specific gravity is approximately 2.6 g/cm³. Natrosilite is often found in association with other sodium-rich minerals, such as albite and nepheline. Due to its rarity, natrosilite has limited economic significance, but it is of interest to mineralogists for its unique structural characteristics and its role in understanding the geochemistry of sodium-silicate systems. It is primarily found in select locations worldwide, with notable occurrences reported in Russia and Norway.