Tanco-Mine

The Tanco Mine is a cesium - lithium -tantalum mine in the Canadian province of Manitoba. The mine is located on the shores of Lake Bernic. The ore consists of a granitic pegmatite ore body. Are degraded mainly pollucite, a Caesiumerz, spodumene, a lithium ore and Wodginit, a tantalum ore. Since 1992, especially pollucite is degraded. The deposit, for decades the world's dominant source of cesium, holds much Caesiumerz that it will be exhausted at constant world consumption only after two to three thousand years.

Geology, reservoir, mineralogy

Pegmatites are igneous rocks in which accumulate by slow cooling of large amounts of incompatible elements. In the lying partly under the Bernic Lake ore body mainly cesium, lithium and tantalum have enriched. The deposit is highly structured, facilitating the breakdown of the various minerals.

After extensive test drilling the pollucite deposit was estimated at 350,000 tons of Cs2O, representing about two-thirds of the world's known reserves. With an estimated consumption of 30 tons per year, the incidence would go back more than 2000 years, although the global demand for cesium wird.Der almost fully covered from this mine degraded pollucite contains about 24 % Cs2O.

History

The pegmatite deposit was discovered in 1929. Although there were several attempts to exploit the deposits, was only in 1969 started with a loss to a greater extent. Until the early nineties, primarily tantalum ore was mined. After 1992, the Cabot Corporation had purchased the mine, especially pollucite was extracted and processed directly to cesium. Cesium formate is used as an additive for the drilling fluid to increase the density. Saturated cesium formate in water has a density of 2.3 g/cm3