How much is a 250 carat diamond cost?

250 carat Diamond- uncertain amount as can be auctioned; very few diamonds of this size

25 carat Diamond- $1 million to $2 million; for a lower quality stone

2.5 carat Diamond - $5,000~$8,000

Another Answer

You can buy a 2.5 carat diamond today on Blue Nile and spend from US$12,000 to US$16,000.

Also, a 15 carat diamond is available on Blue Nile today for just over US1,000,000.