ilmanan

Ilmanan is a rare and unique mineral that was first discovered in the late 19th century in the Ilimaussaq complex in Greenland. It is a sodium-calcium titanium silicate with the chemical formula NaCa2Ti2Si6O18. The mineral is typically found in alkaline igneous rocks and is often associated with other rare minerals such as aegirine and astrophyllite.

Ilmanan is known for its distinctive crystal structure, which is characterized by a complex arrangement of silicon and oxygen tetrahedra. The mineral is usually found in the form of small, dark brown to black crystals, although it can also occur in massive form. It is often found in association with other titanium-bearing minerals, such as rutile and ilmenite.

The name "ilmanan" is derived from the Ilimaussaq complex, where the mineral was first discovered. The mineral is relatively rare and is not commonly found in mineral collections. However, it is of interest to geologists and mineralogists due to its unique chemical composition and crystal structure.

Ilmanan has no known practical applications, but it is sometimes used as a gemstone due to its dark color and distinctive crystal habit. However, its rarity and the difficulty of finding high-quality specimens make it a relatively expensive gemstone. Despite its rarity, ilmanan remains an important mineral for understanding the geological processes that occur in alkaline igneous rocks.