Carat

Carat is often confused with size even though it is actually a measure of weight. One carat is equivalent to 200 milligrams. One carat can also be divided into 100 "points." A .75 carat diamond is the same as a 75-points or 3/4 carat diamond.
 

Carat Ranges
0.08 0.12 1/10
0.18 0.22 1/5
0.23 0.28 1/4
0.29 0.36 1/3
0.37 0.44 3/8
0.46 0.54 1/2
0.56 0.68 5/8
0.69 0.83 3/4
0.96 1.18 1
1.19 1.39 1 1/4
1.45 1.54 1 1/2
1.96 2.18 2

Diamond Mini Guide:  Shape  |   Carat  |   Color  |   Clarity  |   Cut  |   Certification  |   Price