The carat weight of a diamond is a measurement of its weight. One carat is exactly one-fifth of a gram (0.20 g). When a diamond is properly cut, the carat weight defines the size of the diamond. When it comes to smaller diamonds, an Ada concierge may use the term “points” to discuss diamond weights with you. One point is one-hundredth of a carat (0.01). A “33 point diamond” would be 0.33 carats.

3 carat round lab diamond solitaire engagement ring in Yellow Gold Ada Diamonds AD-066

A “buy shy” diamond is one that’s weight is just shy of a major carat threshold such as 1.90ct instead of a 2ct. Just like mined diamonds, lab diamonds are priced mostly by their carat weight, with the price per carat at 1, 1.5, 2, 2.5, and 3 carats at much higher rates than just below those thresholds. Buy shy diamonds are similar in carat weight and may be indistinguishable to the naked eye from a much more expensive alternative. Buy shy diamonds are also very popular and sell fast!



Larger lab diamonds of weights of 2.5ct and are more scarce and difficult to find, particularly in certain elongated shapes such as pears, emeralds, and elongated cushions. Clients seeking a very large lab diamond should not expect to be able to view several options at once and should recognize that this is a supply-constrained, rare product. The largest lab diamond we have ever seen cut and polished was 15 carats!


Lab Diamonds of Different Carat Weights


Explore 1 Carat Lab Diamond Engagement Rings


Explore 1.25 Carat Lab Diamond Engagement Rings


Explore 1.5 Carat Lab Diamond Engagement Rings


Explore 1.75 Carat Lab Diamond Engagement Rings


Explore 2 Carat Lab Diamond Engagement Rings


Explore 2.5 Carat Lab Diamond Engagement Rings


Explore 3 Carat Lab Diamond Engagement Rings


Explore 4 and 5 Carat Lab Diamond Engagement Rings