Some aspects of buying an engagement ring are dependent on your budget, and others are based purely on personal taste. What appeals most to you?

If you choose a traditional ROUND brilliant diamond, the 4 Cs (color, cut, carat, and clarity) are the criteria everyone uses.
The ROUND shape is the most common and the most classic for a solitaire engagement ring. This shape and the PRINCESS CUT shape (square) are the most sparkling.
Other popular cuts are EMERALD, which is rectangular, and MARQUISE. Emerald-cut diamonds have lean, long lines. A diamond solitaire engagement ring with this stone will give you an elegant look which is out of time. The Marquise-shaped diamond visibly makes your stone look larger as if it has more carat weight than a round diamond with the same carat weight.
Other options are: PEAR shape and OVAL shape. A pear-shaped diamond may be an interesting choice for extraordinary personality. Those who like classic but with a little twist can choose oval diamond which also delivers nice brilliance like round ones.
Other shapes include RADIANT, ASSCHER and CUSHION, which are variations of a square.

When you choose a diamond solitaire engagement ring it’s very important to consider the style of the person who will wear this ring. The shape of a stone should perfectly match with her style and look beautiful on her.
As you learn from this tip your choice vary from traditional shapes such as ROUND, ASSCHER, EMERALD or less commun such as PEAR, MARQUISE and HEART.

Once you have chosen the shape, you have to choose the SIZE of the stone. Diamonds are categorized by their carat, which is the weight.
Then look at the quality of the stone. In the case of a diamond, the quality is referred to as CLARITY. The clarity grade is higher on stones that don’t have blemishes and inclusions.

In conclusion, find a stone that has the sparkle and brilliance you desire and remember that the stone’s cut is what affects its beauty. To have something more particular consider to add accent diamonds or other stones to the engagement ring (for example on the shoulders of the ring). It will give more brilliance to your engagement ring.