Cut to an impressive 184.75 carats (from a massive 457.5 carats in the rough), the diamond is known by various names -- the Victoria, the Imperial (both in honour of Britain's then reigning monarch) or the Great White diamond (because of its size and colour).

It was also known as the Jacob because of the famous gem dealer, Alexander Malcolm Jacob, who brokered its sale to Mahboob Ali Pasha, the sixth Nizam of Hyderabad, for pound 150,000.

The Nizam chose to keep the diamond in the sole of his footwear, where it was discovered after his death by his son and successor, Mir Usman Ali Khan. Khan, who was the last Nizam, was then one of the richest men in the world and used the diamond as a paperweight.

At the time of his forced abdication in 1948, the Nizam's collection of jewels was estimated to be worth pound 15,000,000.

After the death of the Nizam's son, Azam, the family decided to sell some of the jewels to meet its huge tax liabilities. But the Government of India decreed the jewels a national treasure and said they could not be auctioned to foreigners.

After lengthy litigation that lasted years (1979 to 1993), the Indian government decided to buy the entire collection. It agreed to pay Rs 218 crores (Rs 2.18 billion), equivalent to about $70 million, for the entire collection; it was reported that the Jacob alone fetched $13 million. The deal was concluded on January 12, 1995.

The Indian government paid $71 million for the collection, which was valued by Sotheby's at $162 million and by Christie's at $135 million.

In 2001, when the collection was exhibited for the first time, it was valued at approximately $2.12 billion. The Jacob was valued at $85 million.

Information courtesy: Internetstones.com