The Jubilee Diamond is a 245.35-carat colourless cushion-cut brilliant of historic importance, cut from a 650.80-carat rough recovered at the Jagersfontein mine in the Orange Free State, South Africa, in 1895. It was named in 1897 to mark the Diamond Jubilee of Queen Victoria, the sixtieth anniversary of her accession in 1837, and is one of the largest faceted diamonds ever sent into the international trade as a stone outside the British Crown Jewels.

Discovery

The rough was found in late 1895 at Jagersfontein, then one of the most productive deep-shaft diamond mines in southern Africa. Originally known by its working name the Reitz Diamond, after F.W. Reitz, then president of the Orange Free State, it was recovered as an irregular octahedral fragment of unusually high purity. The rough was sold by the syndicate of mine owners to a London consortium that included Wernher, Beit and Mosenthal, who in turn arranged for it to be cut at the firm of Metz in Amsterdam.

Cutting

The rough yielded two principal stones: the Jubilee, a 245.35-carat cushion-shaped brilliant, and a smaller 13.34-carat pear shape later sold separately. The Jubilee was cut to D colour and very high clarity. Its cushion form, with a relatively shallow crown and full pavilion, follows the late-nineteenth-century style developed for very large stones, where preserving carat weight is balanced against producing a face-up appearance suited to a single feature stone in a parure.

Renaming and exhibition

The stone was renamed the Jubilee in 1897 in honour of Queen Victoria's Diamond Jubilee, although it was never owned by the British Crown. It was exhibited at the Paris Exposition Universelle of 1900, where it was shown alongside other major diamonds of the period and drew international attention. Following the exhibition it was acquired by the Indian industrialist Sir Dorabji Tata, who had it set as the centre of a parure and used it on state and ceremonial occasions until his death in 1932.

Later ownership

After Sir Dorabji's death the Jubilee was sold to settle his estate. It passed through several private hands in Europe and North America during the mid-twentieth century, including a period in the collection of Paul-Louis Weiller in Paris. In 1966 the stone was lent for the De Beers Diamond Pavilion exhibition at the South African Pavilion of the Johannesburg Empire Exhibition revisitation. It was sold again in the 1980s and is now reported to be in a private collection. Its location is not publicly disclosed.

Significance

The Jubilee occupies a distinctive place among historic diamonds. It is one of the very few stones above 200 carats that combines documented Jagersfontein origin, full D-colour grading by modern standards, and a cushion brilliant cut that was state-of-the-art for its date. Together with the Cullinan, the Excelsior and the Star of Sierra Leone, it belongs to the small group of late-nineteenth and early-twentieth century rough finds whose cutting defined the upper limit of the trade for major stones. It is also one of the principal reference points for what late-Victorian cushion-cut work could achieve from a clean, large rough.