The diamond set in a white gold ring is the hallmark of its visual appeal focusing our eyes on the center stone. Choosing a circular brilliant cut diamond with a carat weight that falls in between 0.30 and 5.00 will round off your engagement ring in fine fashion. A jewelry aficionado may need the ring to feature a large cut diamond set as its center stone against pitch white gold band. While smaller diamond cuts are often set in an arch-shaped setting, which gives a classic feel on the finger. When you look to purchase an 18ct white gold diamond ring you have several cut diamonds to choose from, some of which include: All said and done, your choice of a diamond cut shape in the 18 carat ring would depend on your aesthetic choice and that of your partner’s.