Carat and size
A carat is a unit of weight: one carat is 200 milligrams, a fifth of a gram. It tells you how heavy a diamond is, not exactly how big it looks.
- A carat is split into 100 points, so a 0.25 carat stone is a "twenty-five pointer".
- Carat measures weight, not size: two stones of the same weight can look different.
- Bigger is rarer. In RXXO, 8 in 10 diamonds are under 0.1 carat.
Carat sizes, smallest first
Odds in RXXO- 0.001 to 0.1 ct0.001 to 0.1 ct800,000,000 RXXO diamonds8 in 10
- 0.1 to 1 ct0.1 to 1 ct169,000,000 RXXO diamondsabout 1 in 6
- 1 to 10 ct1 to 10 ct18,121,500 RXXO diamondsabout 1 in 55
- 10 to 100 ct10 to 100 ct11,100,000 RXXO diamondsabout 1 in 90
- 100 to 600 ct100 to 600 ct1,778,500 RXXO diamondsabout 1 in 560
In RXXO
RXXO holds one billion diamonds, approximately a billion carats in all, from 0.001 to 600 carats. Only 10 weigh 590 to 600 carats, close to the largest cut diamond ever recorded.
The biggest RXXO diamonds
Look closer
Magic sizes
Some weights are especially wanted: 1.00, 1.50 and 2.00 carats. A 0.99 carat stone looks almost the same as a 1.00, yet the price can be very different.
The biggest ever
The largest diamond ever found, the Cullinan, was 3,106 carats of rough, found in South Africa in 1905. Its biggest cut stone, Cullinan I, weighs 530 carats and is the largest colourless cut diamond. The largest cut diamond ever recorded is the Black Falcon, a black diamond of 612 carats.
How much is mined
About 118 million carats were mined in 2024. From ancient times to 2005, the world mined an estimated 4.5 billion carats, gem and industrial.
Questions
How much does a carat weigh?
200 milligrams, a fifth of a gram. It is split into 100 points.
Is carat the same as size?
No. Carat is weight. Two diamonds of the same weight can look bigger or smaller, depending on their shape and how they were cut.
What is the largest cut diamond?
The Black Falcon, a black diamond of 612 carats, is the largest cut diamond ever recorded. Cullinan I, 530 carats, is the largest colourless one.
How many points are in a carat?
100. A 0.50 carat diamond is a 50 pointer, and a 0.25 carat stone a twenty-five pointer.
How big can an RXXO diamond be?
Up to 600 carats. Only 10 diamonds sit at the very top, 590 to 600 carats.
RXXO numbers are the odds every mint draws from. Updated 8 October 2026.