Estimated worth: $5.9 billion
From humble beginnings as a carpenter, Dennis Washington built a massive enterprise called Washington Companies that now owns a copper mine, two diamond mines and a regional railroad. And it all started with a $30,000 loan.
Dennis and his wife, Phyllis, started a family foundation with $840 million that has already given out $300 million to some 1,000 different causes. Dennis also invested in his son, Kyle’s, container ship business.