Lucapa Diamond Company Limited today announced an updated JORC Classified Inferred Alluvial Diamond Resource (Lulo Diamond Resource) for the Lulo diamond mine in Angola.

This is  an update on the previous  Lulo Diamond Resource dated on December 31, 2018, and announced on March 21, 2019.  

Outlining the basis on which the updated Lulo Diamond Resource was estimated, Lucapa said that this was done after accounting for:

• 12 months of mining depletion to  December 31, 2019, during which time about 19,000 carats of high-value diamonds were recovered from about 286,000 bulk cubic metres of gravel;

• The delineation of new or additional resources - and improved knowledge of existing resource areas - through an extensive  6,100 hole auger drilling and pitting programme; and

• Diamond sales at prices above the previous resource modelled average value estimate dated  December 31, 2018.

“Notwithstanding the depletion of ~19,000 carats from alluvial mining during 2019 referred to above, in-situ resource carats increased 25% to 100,700 carats in the updated Lulo Diamond Resource,” Lucapa stated. “This total equates to more than five times Lulo’s production of ~19,000 carats in 2019, the fifth consecutive year of commercial alluvial production.”

Moreover, the updated average value of the latest  Lulo Diamond Resource at US$1,620   per carat represents a 14% increase on the previous modelled estimate of US$1,420 per carat.

The overall sales of Lulo diamonds to date total approximately US$168 million at an average price per carat of around US$1,900.

Lucapa Managing Director Stephen Wetherall commented: “The updated Lulo Diamond Resource is the result of another significant workstream undertaken by the Lulo partners throughout 2019 in parallel with the ongoing alluvial mining and kimberlite exploration programs.

“Together with the positive diamond marketing reforms introduced in Angola in 2019, the latest increase in both in-situ resource carats and average modelled price supports the investment made by the Lulo partners to expand diamond production and cash generation from 2020.

“The latest update also represents the highest number of carats ever in a Lulo Diamond Resource – and that is after five years of increasing alluvial mining depletion.

“We are confident we can continue to build on the alluvial resource given the vast areas along the Cacuilo River valley which remain unexplored, coupled with the fact we are now delineating alluvial diamond zones in both the terraces and the flood plain (leziria) areas.

“With that in mind, and with the recent arrival on site of two additional auger rigs, we will see a significant step up in our resource-definition drilling and pitting programmes in 2020.”

Sociedade Mineira Do Lulo (Lucapa 40% associate and operator) carries out the alluvial mining at Lulo.

Presently, the Lulo partners are conducting an expanded pitting and auger drilling programme around the known diamond areas at Lulo, in order to grow the Lulo Diamond Resource. “This programme has allowed known alluvial channels to be defined with much higher confidence,” Lucapa said. “This has, in turn, seen the exclusion of some of the lower value areas which were previously included in the resource, resulting in an increase in the updated diamond grade and value.”

Lucapa said the resource-delineation programme will be further expanded during 2020.

Pic Cap: Resource-definition auger drilling at Lulo

Pic Courtesy: Lucapa Diamond Company Limited