The Diamond Hunters by Wilbur Smith
The tall wave of green water that raced across the pit hit the Land Rover, upending her, throwing Johnny into the jubilant frothing water, while the Land Rover rolled over on her back, pointing all four wheels to the sky in surrender. Johnny went under. Some people will never have enough . . . Johnny Lance, taken in by the Van Der Byls when he was an orphaned boy, has always done everything to please the Old Man and his adoptive siblings: jealous Benedict and smart, beautiful Tracey. But a terrible misunderstanding means the Old Man has spent decades trying to destroy Johnny - a legacy that continues even after the bitter patriarch's death. Manipulated into giving everything he has to the Van Der Byl Diamond Company, Johnny realises he only really needs two things in life: his good name, and to be with Tracey. But an obsessive Benedict has been shaped at his father's hand, and will do anything to ensure Johnny fails. Even if it means the end of them all . . .