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Diamond Carat

by David Weliver

A diamond’s carat weight is the gem’s size. (A carat is a metric unit of weight equal to one fifth of a gram.)

The larger a diamond’s carat weight, the more valuable the stone will be. As diamonds get larger and larger, the price of the stone will increase exponentially, as diamonds larger than a few carats are exceptionally rare. Fortunately, you will find plenty of diamonds to choose from in many sizes ranging from a quarter of a carat (0.25ct) to 2.0 carats or more.

What Size Diamond Should I Choose?

For better or worse, a diamond’s size is one of the first things people notice. So there is some logic in springing for the largest stone you can afford. That said, you need to consider all of the four C’s. A larger diamond with a fair cut, for example, may cost the same as a smaller diamond with an ideal cut, but won’t have the same sparkle.

For a solitaire engagement ring, a 1.0 carat diamond is a good starting place. If you can’t afford a full carat, smaller stones with high color and clarity grades will make up in sparkle what they lack in size. You can also opt for a setting that surrounds the one stone with smaller stones giving it a larger appearance.

Comparing Sizes

Here are two engagement rings from Blue Nile that showcase the difference between a smaller and larger carat diamond.

Round 0.35ct. Diamond
.35 Carat Round Diamond on a Platinum Band
1.01 Carat Round Diamond on a Platinum Band
3.63 Carat Round Diamond on a Platinum Band

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