Holding an international diamond conference in Zimbabwe was always going to be controversial.
For years there have been media reports of alleged human rights abuses at Marange, allegations of millions of dollars going into pockets of senior government officials and army chiefs.
Government officials have always denied this. Access to the diamond fields is difficult, it's hard to say what exactly is going on over there.
Everytime I have asked for permission to visit Marange as a journalist, it has always been a "no".
But despite the secrecy, business must go on and all the big names in the diamond industry are in the resort town of Victoria Falls.
President Robert Mugabe's government is trying to win international respectability for its gem trade. Countries like China and India, for example, are tapping into the market.
According to officials Zimbabwe's eastern Marange field – one of the world's biggest diamond deposits – has been mined since 2006.
Its vast earnings could have turned around Zimbabwe's economy, battered by years of meltdown and political turmoil.
But funds from the diamond sales have not showed up in the state treasury. The Finance Minister Tendai Biti always complains about this - he says the country can't afford to provide essential services to its people, jobs, food and pay government employees their salaries.
But this is not the only example in Africa. I was recently in Ivory Coast and managed to visit a diamond field.
Soldiers guard people digging in the pits - mainly women and children.
Everytime someone thinks they've found something they raise their hand. A soldier comes over and takes it away.
It's not possible to ask the women how they feel about working here or how much they earn - everyone we try to speak to tells us they are happy.
I don't blame them for being cautious... If I had soldiers holding guns watching my every move, I would be afraid too.
A UN export ban means Ivory Coast cannot legally sell its diamonds. Human rights groups say most are smuggled out and sold on the black market.
The village they live in has no electricity, running water or decent homes.
The point I am trying to make is monitoring the world's diamond fields is not always easy.
When billions of dollars stand to be made, some people prefer profit over human rights.
Will the international conference in Zimbabwe make a difference - or will it be another meeting that promises to make the world a better place, but never quite manages to do that?
Follow Haru Mutasa on Twitter: @harumutasa