There was once a song, its tale ancient and origins unknown; but a rough translation is still recited and sung by a few bards today.

She calls down to me, my radiant muse, voix celeste
With pure of voice and touched by light, voix celeste
I would find her still, buried deep beneath, voix celeste
Eridanus guide me so, that I may join you, voix celeste
There have been a number of notable scholars and thinkers who have referenced this specific passage in recent years. Some believe that the person in the tale speaks of the highly sought after gifts of the Lifebringer; the Shards.

Approximately two centuries ago, the Radiant era began.

The cause and subsequent naming of this era came about because of a strange and beautiful event. The Lifebringer cycles, very slowly and over many hours the grand sphere will pulse with light and warmth giving the lands that surround it sustenance and the people that live on those Isles a period of day and night. However it would come to pass that during one of these night cycles, the strange markings that scatter across its surface would begin to act erratically, some tales even speak of dancing lines and flashes of incredible colours. The stories of this night vary wildly, with some even believing they, or someone they know, had seen a face of the Lifebringer shatter completely. What is truly known and well documented however is that on the subsequent days after this event the mortals of Bastion would begin to see strange bright and radiant shards slowly drifting down from the sky above.
Many of these beautiful objects would simply pass by the Bastion and out into the fathomless and ever present Elemental Chaos. But of course some few would find their way onto the majestic and waiting Isles, where mortals had been watching on in awe and reverence.
It wouldn’t take long for some of these beautiful objects to find their way into the waiting hands and eager eyes of various nobles, practitioners, scholars and inventors alike. Of course not everyone was so keen on the idea that mortals should be handling such objects, with many believing that they may be part of some religious test or prophecy. Motivating some groups and individuals to try and hide the shards, or otherwise keep for worship and spiritual understanding believing them to be some sort of religious artifact or gift.
Whatever the true case may be, these shards immediately became highly sought after and immensely valuable, even more so once some of their strange properties began to be somewhat understood.