pargasiteferropargasite

Pargasiteferropargasite is a mineral belonging to the amphibole group, specifically a variety of pargasite. Its chemical formula is generally expressed as NaCa2(Mg3Fe3+)(AlSi6O22)(OH)2, though variations can occur. This mineral is characterized by the presence of iron (Fe3+) in its structure, distinguishing it from pure pargasite. It typically appears in shades of green, brown, or black.

Pargasiteferropargasite is a relatively rare amphibole, often found in metamorphic rocks such as skarns and high-grade schists. It can also occur in some igneous rocks, particularly alkaline and peralkaline intrusions. Its formation is associated with high-temperature and moderate-pressure conditions. Gemological interest in pargasiteferropargasite is limited due to its rarity and common occurrence as an accessory mineral rather than a primary gemstone. However, when found in suitable clarity and color, it can be of interest to collectors.

The crystal structure of pargasiteferropargasite is monoclinic, similar to other amphiboles, and it typically forms prismatic or acicular crystals. Its optical properties include pleochroism, meaning it exhibits different colors when viewed from different angles. The refractive indices and birefringence are characteristic of the amphibole group. Due to its iron content, it may exhibit magnetic properties.