This is a popular design that we have been doing in remounting a marquise.
The clean lines and modern design freshens up a diamond shape that was very popular in the 80’s/90’s. The fashion pendulum always swings and the marquise may see a revival.
Channel setting the marquise on it’s short side is unconventional. I would not suggest setting it this way in a ring. A pendant or earrings don’t take the abuse that a ring undergoes. In a ring, the exposed points of the marquise would catch on things and would constantly teeter-totter itself loose.