Gaddafi was the single biggest gold owner in the world (!). And Libya was the state in Africa with the highest social standard. That doesn't necessarily mean Gaddafi was a good guy. The EU paid him 3 billion € every year to keep the refugees away from Italy. And he used to say that Europe would collapse by the amount of refugees once he wouldn't be there (which is exactly what happened). When Gaddadi, just like Saddam Hussein, announced that he rejected the US$ and was thinking about a new gold-backed currency, he signed his own execution.

As oil is traded in $ (for which there is no reason), every country in the world has to have $, which produces a permanent high demand for this currency. The Dollar is thus totally overrated and if Hussein and Gaddafi had succeeded, the $ would have gone into free fall.

Long story short: Hitlery and Sarkozy (French president at that time) decided to have Gaddafi killed, refugees have been flooding Europe ever since, the once prosperous Libya is a failed state with slave markets and Gaddafis huge gold reserves have disappeared. That's called to kill several birds with one stone.