Cesium or Caesium is one of the most reactive and quite unusual metals on earth. In fact, it is an alkali metal that’s pretty rare. In addition, it’s soft and has a very low melting point. In fact, it would probably melt in your hand at no more than a room temperature – if it doesn’t explode first because it’s highly reactive to moisture.
The only metal that can be more active than Cesium is Francium, however, the differences between these two are too vast to be compared. Nevertheless, Cesium itself is very ductile and has nearly twice the density of water. When it comes to the price, this element is considered as more precious than gold. A gram of it can cost up to 100 euros. But be that as it may, a considerable amount is wasted here, in the video below, where a Youtuber does some crazy Cesium experiments.
Check it out!