Russian mining giant Alrosa is set to auction off a huge 51-carat "Dynasty" diamond and four other high-purity diamonds with a starting price of $10 million, the company says.

The five-diamond collection seen by AFP correspondents on Thursday was cut from a 179-carat rough diamond discovered in 2015 in one of the state-owned company's mines in the Sakha region of eastern Siberia.

Alrosa, Russia's top diamond producer, calls the 51.38-carat gem that is the centrepiece of the collection "the largest and purest diamond cut in the history of Russian jewellery making".

"All five diamonds were manufactured from one rough diamond, which is an exceptional case. It took a year and a half to create the collection," Alrosa's president Sergei Ivanov said in a statement.

The largest diamond in the collection was named in honour of Russia's last imperial family the Romanovs, whose rule ended a century ago in 1917 with the abdication of Tsar Nicholas II. The other gems are named after Russian aristocrat families.

The second largest diamond in the collection measures 16.67 carats, while the smallest is 1.39 carats.

After going on a tour taking in several countries, the collection is expected to be auctioned off in November via Alrosa's website.

"Based on the auction results of Sotheby's and Christie's, the starting price of the collection can be no less than $10 million," Ivanov was quoted as saying by the Interfax news agency.