Carat Weight in Diamonds: Definition, Points, and Value Impact

Carat (ct) is the unit of weight for diamonds and gemstones.

• 1 carat = 0.2 grams = 200 milligrams.
• 1 carat = 100 points (so 0.50 ct = 50 points).

Value Impact

Carat weight is one of the 4 Cs (cut, clarity, color, carat) determining diamond value. Price increases exponentially at certain "magic sizes" (e.g., 1.0 ct, 1.5 ct, 2.0 ct). Diamonds over 1 carat are considered "large" and command a premium per carat.

Note: Carat measures weight, not size (diameter). Two diamonds of equal carat can appear different sizes depending on cut proportions.