Numerous artificial radioactive isotopes have been produced. Cesium is a soft, ductile metal. It’s hard to get a world market price on cesium because there is no trading of this strategic metal, but according to the most recent Mineral Commodities Summary, one company offered 1-gram ampoules of 99.8% (metal basis) cesium for $63.00, a slight increase from $61.80 in 2018, and 99.98% (metal basis) cesium … In May 2018 Cesium … Only one stable isotope of cesium occurs naturally — cesium-133. Cesium was discovered spectroscopically in 1860 by Bunsen and Kirchhoff in mineral water from Durkheim. The metal is cesium (Cs), the most active metal on Earth, and it’s so rare that it’s hard to even put a price on it. It’s also a vital ingredient in our ability to make 5G happen. The metal is Cesium, and it’s quite possible you’ve never even heard of it–yet, global dominance, which depends on technological superiority, can’t happen without it. The metal is Cesium, and it’s quite possible you’ve never even heard of it--yet, global dominance, which depends on technological superiority, can’t happen without it. It is readily drawn into fine wires. … Sources. Cesium, an alkali metal, occurs in lepidolite, pollucte (a hydrated silicate of aluminum and cesium), and in other sources. One of the world's richest sources of cesium …