The Moussaief Red Diamond was discovered in 1990 by a Brazilian farmer.  It was found in the Abaetezinho River which runs through a region known as Alto Paranaiba.  This region is well known as a source of large fancy coloured diamonds.  

When found the rough stone weighed 13.9 carats. The William Goldberg Diamond Corporation purchased and cut the diamond which was then known as The Red Shield.  

The cut diamond now measures 5.11 carats and is a triangular brilliant cut diamond, sometimes referred to as a trilliant cut.  It is rated in colour as a Fancy Red by GIA (Gemological Institute of America) and is the world's largest known red diamond.

Between 2001 and 2002, the diamond was purchased by Shlomo Moussaief, an Israeli born jewellery dealer in London and currently owned by Moussaief Jewellers Limited.

Image from GIA.edu