The Blue Diamonds were a Dutch 1960s rock and roll duo, best known for their million-selling chart-topping single, "Ramona".Indo (Dutch-Indonesian) brothers Ruud de Wolff (12 May 1941 – 18 December 2000) and Riem de Wolff (15 April 1943 – 12 September 2017) founded the group shortly after immigrating to Driebergen-Rijsenburg in the Netherlands in 1949.They were born in Batavia (now Jakarta), Indonesia.