The circular shape of the round diamond is said to signify love without end. The sentiment may be why it is the most popular diamond shape for engagement rings. The round diamond accounts for more than 75 percent of all diamonds sold. Why are round diamonds so popular? Because a round diamond’s brilliant cut which gives it the ability to optimize light reflection makes it brighter and more brilliant than all other diamond shapes. Round diamonds, because of their faceted cut, are also referred to as brilliant or as round brilliant cut because round diamonds are the most common of the brilliant-cut diamonds. A round brilliant diamond will have 58 facets, which cause light to bounce from the bottom of the diamond and back up through the top, giving it unbelievable sparkle.