This, however, came after authorities in Tanzania blocked a parcel of diamonds (71,654.45 carats) mined at the Williamson mine from export to Petra's marketing office in Antwerp.
Tanzania claimed that the diamonds were worth $29.5 million, but Petra had under-declared the stones for export.
Dar es Salaam said it had ordered a fresh sorting and valuation of the diamonds to ascertain if the actual value was declared and all relevant taxes were paid.
However, the diamond company said that it was not responsible for the provisional evaluation of the stones.
“Petra is not responsible for the provisional valuation of diamond parcels from Williamson before they are exported to Antwerp; this is carried out by the government's diamonds and gemstones valuation agency,” it said in a statement.
“This provisional valuation is used to calculate the company's provisional royalty payments to the government, however adjustments to final royalty payments based on the actual sales proceeds for the diamonds, once sold in Antwerp, are then made at the end of the tender process.
“The competitive open tender process utilised by Petra is also used by several other diamond mining companies and has a proven track record of transparent price discovery.”
Tanzania said it had ordered a criminal investigation to be launched against all officials involved in declaring the value of the diamonds and issuing export permits.
President John Magufuli ordered last week a review of Petra Diamonds’ contract as officials claimed that the country was likely losing more than $46 million each year from the export of under-cleared diamonds.
Mathew Nyaungwa, Editor in Chief of the African Bureau, Rough&Polished