A Kinshasa-based trader's gems could come from several places

While an expert can source a parcel of rough diamonds, his job is close to impossible once the parcel has been broken up.

In trying to come up with a solution for identification, experts have suggested the use of verifiable samples of diamonds.

In this case a profile or duplicate diamond from official mining areas could be made in order to isolate a conflict diamond from a 'clean' diamond, or what de Beers calls a development diamond.

For this to work the diamond industry will require government co-operation.

Angola

In the case of Angola, where Unita rebels dig for diamonds, the government would have to provide military information regarding the location of the rebels.

Divers retrieve diamonds from rivers in Unita-held territory

Luanda correspondent Lara Pawson say this may not be easy.

Critics point out that Unita, as a guerrilla force, is constantly on the move, relocating its position throughout the country on a monthly, weekly or even daily basis.

De Beers state, however that the location of official mines, not the rebels, is the issue.

Nevertheless, 50% of Angola's diamond production comes from individual diggers known as guaranteros.

Currently there are 47 buying offices scattered across various parts of the country where guaranteros can sell their stock.

Experts in Luanda agree that UNITA diamonds leak through the buying offices despite the recent creation of Ascorp, Angola's selling corporation.

How to stop this and how to implement an effective certification system will be debated in Windhoek, three weeks prior to the Southern African summit on conflict diamonds due to be held in Pretoria.