CEO Johan Dippenaar holding the exceptional 122.52 carat
blue diamond recovered in June 2014. Photo from Petra
A rare 122.52-carat blue diamond found in South Africa
could fetch more than $US35 million for a London-listed mining
Only three or four blue diamonds over 100 carats have ever
been recovered, according to Cathy Mallins, corporate
communications manager at Petra Diamonds Ltd.
So far, the highest price on record for a rough diamond is
$US35.3 million, paid in February 2010 for a 507-carat white
stone recovered from the same mine, finnCap analyst Martin
Potts said in a research note.
"We think that this stone may break that record," he said.
Both diamonds were recovered from the Cullinan mine, the
source of many large diamonds, including the largest rough
gem diamond ever recovered - the 3,106-carat Cullinan Diamond
found in 1905.
That diamond was cut into two stones that are part of
Britain's Crown Jewels held in the Tower of London.
Petra's shares rose as much as 7 percent on Friday, making
them the top percentage gainer on the FTSE-250 Midcap Index .
Petra said it would evaluate the optimal route to market the
stone after further analysis to assess its potential value.
Last month, a 100-carat yellow diamond fetched $US16.3
million at a Sotheby's auction in Geneva - the highest amount
ever paid for a diamond of that colour. The rough stone was
"Given that blue diamonds are rarer, more desirable than both
yellow and white stones, we would expect multiples of this in
terms of value," Numis analysts said in a note.
"If it comes back from analysis as 'fancy vivid' colour then
it could blow the roof off."
Other notable diamonds discovered at the mine include the
25.5-carat Cullinan blue diamond found in 2013, and sold for
$US16.9 million, and the Star of Josephine diamond recovered
in 2008, which sold for $US9.49 million.
Petra bought Cullinan in 2008. The mine, located at the
foothills of the Magaliesberg mountain range north-east of
Pretoria, is one of the company's five producing mines in
South Africa. It also has mine in Tanzania.