The other three are Mbada Diamonds, Diamond Mining Corporation and Anjin.
Security officers said according to the stringent Kimberley Process Certification (KPC), he would have to undergo rigorous security vetting before he could be released.
They said the earliest he could be released was today.
Matenga was part of a group of journalists and members of the civil society who were on a tour of the Marange Diamond fields.
At several points during the tour, the strict security requirements were explained by officials from the Zimbabwe Mining Development Corporation and officials from the diamond mining companies.
“There are cameras everywhere. If you drop anything, do not pick it. Ask security officers to do it for you. You will be thoroughly searched at every point and random searches are conducted to ensure maximum security,” was the message that was repeatedly told to the tour group.
However, Matenga was found with a brown stone in one of his pockets when security officers conducted a body search.
Colleagues said it was a stone that he often carried around with him.
Others speculated that he wanted to prove that security was lax at the mines by going through every search point with the stone.
Journalists and members of the civic society tried to negotiate for his release but security officers said it would be a breach of one of the security requirements that were agreed on at the certification of the diamond mines.
“He will have to be vetted by the minerals department of the Criminal Investigations Department (CID), the ZMDC, Zimra, internal security and the commissioner of mines. Written reports would have to be submitted to all these authorities and it has to be determined what kind of stone it is and where he got it from, before we can talk of releasing him,” said a security officer who declined to be named.
“Sorry, that is the law here and there are no exceptions,” he said.
The chief executive officer of Marange Resources, Mr Obert Dube, could not be reached for comment.



