[@Sophrus]

They're from Solaria, one of the Original Twenty, and a lost world. Solaria is to 26M Humanity what Atlantis is for us. They are essentially a dead race as their are no full Solarians left. Hence half-solarians or quarter solarian (even these are exceptionally rare and more a point of pride for Noble families to show how ancient they are). 

Solarians themselves have become the stuff of myth and legend. However a few characteristics are seen in individuals with half solarian blood. Glassy silver or purple eyes. Tall. Strong for their builds. Often possessing fair hair or stark black along with fair complexions. Solarian artifacts are often priceless and rare, with only a few being able to be used it seems or in functioning order.