Obviously the fewer of inclusions that exist in a stone, the more expensive the stone will be. Keep in mind that there are very few diamonds that exist without inclusions. Also remember that no two stones have inclusions that are the same. The cut of the diamond is usually a matter of preference. Popular cuts include the marquise, the round, and the pear.
Baguettes are also a popular stone cut.
A diamond that is well cut will reflect more light and thus sparkle better than others that are not well cut. If you are not choosing a diamond, or find a stone and need a mounting, check out the various kinds available. The mounting for your stone or the wedding bands you may choose can be varied. Depending on your budget, you may choose 10K gold, 14K gold, or even 18K gold. You can also have the precious metals brushed or textured to add a unique look to your rings.