Kalvens
Kalvens are a hydrated silicate mineral described as a distinct species in regional geological classifications. The name derives from the Kalven region, where the mineral was first documented in the early 20th century. The term also encompasses closely related varieties with similar composition and structure.
Chemically, kalvens feature a layered silicate framework with interlayer water and trace amounts of iron, magnesium,
Geologically, kalvens form in hydrothermal veins and pegmatites associated with granitic or volcanic rocks. They are
Extraction and processing are mainly open-pit in shallow deposits and underground for deeper pockets. Rough kalvens
Uses and research: The principal commercial use is as an ornamental gemstone and decorative stone. Studies