There never was any question when it came to cesium whether it would be available as a proper cube. In addition to its voracious reactivity the metal is creamy soft and melts at body temperature. Filling a boxy class cube with internal dimensions equaling a cubic centimeter is as close as we’re going to get with this one!

Cesium - or caesium if you’re British - is one of only three unambiguously colored metals besides copper and the gold which it resembles. Side by side with gold, however, they’re easy to tell apart because cesium is more pale. It is in fact closer to brass than gold. Of course, it can only be appreciated behind glass as even momentary exposure to air will turn it black almost in an instant while contact with water will start a little impromptu fireworks show. In addition to its similar appearance, also being nearly as expensive as gold keeps this pretty element out of reach from naughty kids who would otherwise toss it into the water for the giggles. There’s always sodium for that ;-)