Diamond Carat is the most visual of the 4 C’s of diamonds. Carat is a weight measure for a diamond that is globally recognized. Not to be confused with karat (a measure of gold purity), a 1.00 carat or ct diamond weighs 0.20 grams. Contrary to popular belief, the carat is not the size of the diamond. The size of a diamond is measured in millimeters by length and width. It typically takes about 250 tons of rock mining to produce just 1.00ct of diamond. That is why diamonds are rare and expensive. Diamonds come in a variety of shapes and carat weights. A diamond cutter’s highest priority is to maximize carat weight of a diamond. The larger the diamond, the rarer and therefore more expensive it is. Diamonds are weighed with carat/gram scales very precisely to the 0.01ct.
Carat Price Effect
Diamond pricing increases exponentially, not linearly, as diamond carat weight increases. Once a diamond hits it’s critical weight, the price bumps up. The critical weights are: 0.30ct, 0.40ct, 0.50ct, 0.70ct, 0.90ct 1.00ct, 1.50ct, 2.00ct, 3.00ct, 4.00ct, 5.00ct, 10.00ct. Diamond cutters will do everything they can to keep the diamond weight at or above each critical weight. Therefore, while it is often recommended to purchase 0.95ct diamonds vs. 1.00ct diamonds, it’s very difficult to find 0.95ct diamonds. Additionally, diamond manufacturers and suppliers know this “trick” and so they’ll price their diamonds accordingly.
The average diamond carat weight is 0.90ct. Consumers prefer Carat above the other C’s of diamonds because carat is the most visual C. When pricing diamonds, think about carat on one side and the other 3 C’s on the other side. In order to fit your diamond budget, as you increase carat, you may need to reduce the other C’s. Vice versa, if you increase the other C’s, you may need to decrease carat.
Please see our diamond price estimator to understand the approximate pricing across a variety of diamond sizes, when combined with the other diamond attributes.