The second piece is one of the most important parures of antique coloured diamond jewels to appear at auction in the last 50 years. This superb suite contains stones which may have formed part of a gift by Empress Catherine I of Russia (1684-1727), wife of Peter the Great to Sultan Ahmed III to negotiate the end of the Siege of Pruth in 1711. By tradition, these extraordinarily rare jewels were then used by the Sultan Abdul Hamid II (1842 – 1918) for the present necklace, which he offered to the wife of Teufik of Egypt, possibly for the birth of the last Khedive of Egypt and Sudan in 1874. The parure will be offered in November with a pre-sale estimate of $3-5 million.

“These two stunning jewels carry with them a fascinating insight into the luxury and opulence of the Russian court. It is difficult to overstate their rarity and historical importance, and I am thrilled to be able to present them side by side this autumn.“ David Bennett, Worldwide Chairman of Sotheby’s International Jewellery Division.

OPULENCE AND CRAFTSMANSHIP: THE RUSSIAN CROWN JEWELSRussia’s Diamond Treasure was founded in 1719 by Tsar Peter the Great (1629 – 1725), to distinguish the vast wealth of the Romanov dynasty. He is known to have commissioned numerous elaborate jewels as gifts for his wife, Empress Catherine I (1684 – 1727). Stored in the so-called Diamond Room of the Winter Palace in St Petersburg, this breathtaking collection of state jewels and regalia was added to by successive rulers, as instructed by Peter himself. The largest contribution was made by Catherine II, known as Catherine the Great (1729 – 1796), who ruled as Empress of All Russia from 1762 to 1796.

DIAMOND JEWELS “IN A CLASS OF THEIR OWN“Thought to have been part of the Collection of Catherine the GreatThe jewellery collection of Catherine the Great was renowned, and never equalled before or since in Russia. Her jewels and regalia proclaimed her power and rank as Empress and displayed the most precious materials available, crafted by the most highly skilled French jewellers such as Pauzié and Duval. This piece was originally designed as two separate jewels, crafted around 1760-80. Stylistically, the two pieces are consistent with traditional designs of the late 18th century, which would have been fastened around the neck using a ribbon or stitched directly onto clothing.

At the outbreak of the First World War, the decision was made to move the imperial treasure from St Petersburg to Moscow, and the jewels were stored in sealed cases in the Kremlin. A number of jewels – including the present necklace band and bow knot brooch - were taken to London and offered at auction at a sale of “The Russian State Jewels” in 1927. They have only been in two private collections since then, including that of the present owner.

After the war, a commission was formed to itemize and value the jewellery collection of the Romanovs from the early 17th century onwards and a catalogue, entitled Russia’s Treasure of Diamonds and Precious Stones, was published, in Russian, English, French and German, under the supervision of Professor A.E. Fersman. This autumn’s sale will include one of the very rare surviving copies of this catalogue with an estimate of $38,000- 51,000 (The Bolshevik government recalled and destroyed most copies of this catalogue, hence its extreme rarity).

A SUPERB SUITE OF IMPERIAL JEWELSContaining stones from a jewel which may have been used by Catherine I, wife of Peter the Great to end the Siege of Pruth in 1711Dating from the mid-19th century, this diamond parure is comprised of a necklace, a brooch and a pair of earrings. It contains stones which may have formed part of a gift presented by Empress Catherine I to the Twenty-Third Ottoman Sultan, Ahmed III (1673-1736) as part of peace negotiations with Czar Peter the Great, after the Pruth River Battles in 1711.

According to an account by Voltaire in his History of the Russian Empire under Peter the Great (1759), following days of siege, Catherine urged her husband the Czar to pursue a peaceful outcome to the stalemate. Knowing the importance of the Oriental custom according to which one should never approach a sovereign or their representatives without gifts, Catherine gathered all the jewels she had brought with her, including family heirlooms and gifts from her husband. Secretly, she sent them alongside the Czar’s letter to the Grand Vizier. Sultan Ahmed II accepted the sumptuous gift and a peace treaty was agreed between Russia and the Ottoman Empire.

Following their crucial role in the history of these two empires, these imperial Russian jewels are believed to have then passed into the Ottoman Treasures. By tradition, they are said to have been used by the Sultan Abdül Hamid II (1842-1918) in the commissioning of the present parure, which he presented to the wife of the Khedive Teufik of Egypt, possibly on the occasion of the birth of their son and heir Abbas II Hilmi Paşa (1874-1944). Born HH Princess Emine-Nacibe Hanimefendi, the "Valid Sultan" or "Valide Pasha" became the most powerful woman of the region, seconding her son in the conduct of the State until 1914, when Egypt became an independent Sultanate under a British protectorate.