The diamond, weighing a staggering 709 carats, is among the 20 biggest diamonds to ever be discovered in the world.
It is being kept locked away in Sierra Leone's central bank in Freetown.
The diamond presented the diamond to the country's president who thanked the local chief for not smuggling the diamond out of the country.
President Ernest Bai Koroma said that Pastor Emmanuel Momoh would get "what is due" to him but that any profits from the diamond will benefit Sierra Leone as a whole.
The largest diamond to ever be discovered is "Sergio" which weighs 3167 carats. The black diamond was discovered in Brazil in 1893.