How many cts is the biggest diamond in the world?

Answer 1

Uncut, the largest raw diamond ever found was over 3,000 carats.

You can read more about large cut stones and their carat weights on the link, below.

Answer 2

The largest diamond in the world is the Cullinan diamond, which was discovered in South Africa in 1905. The Cullinan diamond weighed 3,106 carats in its rough form and was later cut into several smaller diamonds, with the largest finished diamond known as the Great Star of Africa weighing 530.2 carats.