It’s weird how the ancient Latin word for sky, caelum, should somehow yield a word that today sounds like ‘sea-lum’ but they’re the same guys after all who came up with Caesar. We’re just not used to the s-sounding C when followed by an A. This is why at some point back in the 1800’s our great-grandparents here in the U.S. dropped the letter and have been writing cesium ever since… much to the chagrin of the British (and really, the rest of the world) who view this as lexical sacrilege.

Regardless, what does the sky have to do with this golden-toned metal? Well, the discoverers of the element never had the joy of seeing the pure metal. Shortly after the discovery that light shone through a prism yields different colors according to the elemental makeup of the source, it was only natural that the nerds of the day would start burning samples of different ores to see if anything cool happened. And something cool did indeed happen when they set a sample of pollucite to the candle. The blue portion of the spectrum shone much brighter here. The Victorian-era chaps knew they had their first hit and wasted no time in naming this blue light generator after the color of the sky. The same method would soon after yield indium (after the color indigo) and thallium (after Greek for ‘greenish’). Not terribly creative when it came to names but this was an era when every other kid was named John or William so it shouldn’t be too shocking.

To repeat, these guys never saw the decidedly non-blue color of the element they discovered. And it wasn’t for lack of trying. Metallic cesium is quite difficult to prepare because of its sky-high (heh) affinity to combine with other elements. It’s a bit like unsticking two tiny magnets from each other. The only effective way to pry it off is to find another chemical with an even higher affinity to the offending atom that it can tease it away from the Cs one.

For the purposes of a collectible such as the one offered here, even the minutest trace of contaminants can spoil the show. These vestigial impurities act as nucleation points on the glass walls turning it messy and obscuring the view. Extraordinary steps must be taken to chase away as many of the non-cesium atoms as possible. Not surprisingly, this raises the cost of an already costly commodity. This is a shame as practically every fan of the elements would love to have one of these if only it were more affordable.