Vivianite

Unknown Owner

Lustrous gemmy green to slightly blue prismatic crystals of vivianite to 2.0 cm in length coming off matrix. Beautiful when backlit as seen in the picture and at the end of the video. In very good condition. Choice miniature for the species.The Huanuni Mine is located in the Dalence Province of the Oruro Department, Bolivia, though it is often associated with the broader high-altitude mining regions near Potosi. Established in the late 19th century and later becoming a centerpiece of the state-owned mining company COMIBOL, it is one of the largest and most productive tin mines in the world. Geologically, the deposit is centered on the Posokoni hill, consisting of a complex system of hydrothermal veins hosted within Paleozoic sedimentary rocks, specifically quartzite and shale. These veins were formed by mineral-rich fluids associated with the intrusion of igneous bodies during the Miocene epoch. While primarily mined for cassiterite, the mine is world-famous among collectors for its extraordinary vivianite crystals. These iron phosphate minerals form in low-temperature, phosphate-rich environments within the oxidation zones and lower mine levels. The vivianite from Huanuni is prized for its intense deep green to emerald color and its ability to form large, transparent, prismatic crystals that are often considered the finest of their species.