One of the rarest diamonds available on the market is set to go under the hammer at christie's semi-annual auction in Geneva.
The "Oppenheimer Blue" is the largest diamond of its kind to be offered on a public sale.
The rectangular cut diamond weighs 14.62 carats and has been graded by the Gemological Institute of America as "fancy vivid blue."
That means its blue color ranges from medium to dark in tone.
The worth of the diamond is estimated between 38 and 45 million dollars.
The "Oppenheimer Blue" was previously owned by Sir Philip Oppenheimer, who belonged to the family which ran the De Beers mining company.