Hope Diamond
This is best known for its supposed curse. A blue colour, the Hope Diamond came from India, and was sold to the French King Louis 14th in 1668. It disappeared during the French revolution around 1792, with its royal owners being beheaded. This is recorded case of its owners being killed.
The next known owner, King George 4th of England, had to sell it to pay his debt; the next owner, Henry Phillip Hope (after whom the diamond was named) died in poverty, as did his whole family. Over the following decades many deaths, insanities and suicides were connected with the gem. It has been in the Smithsonian for the last 4 decades, with no further reports of accidents or misadventure.
Before being named ‘the Hope’ this diamond many have weighed an estimated 115 carats. It was cut to 45.5 carats to avoid identification.
Cullinan Diamonds
The largest rough diamond ever found, this was originally over 3000 carats. Discovered in 1905 the rough diamond was cut into nine large and many smaller stones a few years later. The largest of these, called the, Cullinan 1, weighed 530 carats, and was for many years the largest known cut diamond in the world