The Excelsior rates as the fourth largest rough diamond of gem quality ever found.

The Excelsior Diamond was found on June 30, 1893, at the Jagersfontein Mine in the Orange Free State, one of the South African Republics during the second half of the 19th century, by a worker in a shovelful of gravel he was loading into a truck.

Instead of handing it over to his overseer, he delivered it directly to the mine manager, who rewarded him with £500 in cash and a horse equipped with a saddle and bridle.

This may have contributed to the fact that its discovery was not reported in any of the prestigious British newspapers, and the diamond, despite its fine quality and exceptional size, remained largely unremarked upon.

It did contain a number of black carbon inclusions, which are typical of the diamonds from the Jagersfontein mine.

It was cut without regard to its historical significance, divided into small, easily sold assorted stones.