 Founder Jean-Raymond Boulle and top UK insurer Prudential plc had owned 10% and 14% stakes in Adastra, respectively.In the mid-1990s, the company became known for developing highly prospective copper and cobalt mines in Zaire during a civil war.American Mineral Fields (AMF) was founded in 1995 to "develop diamond interests" in Brazil by Mike McMurrough and Jean-Raymond Boulle.