PLATINUM is a magical material very light color, high density and almost unalterable. In 2020 I would advise – Buy Platinum! Read more about using platinum here.
BLACK TANTALUM is an absolutely fantastic metal, one important key point to the Cedric Chevalley’s design success. Read more about Black Tantalum here.
INVISIBLE a perfect setting for only taking advantage of the stone.
FLAT sides make an impression of having a thicker ring, it make the side more presents. In both cases, flat or roundish sides, to provide comfort, we break the edges by making a radius instead of leaving a sharp edge. In this case, of flat sides, the radius are small and the sides stay flat as much as possible.