This announcement from Gem Diamonds follows the recent Letšeng recoveries announced in May of an exceptional 80.58 carat D-colour Type IIa diamond and a 98.42 carat D-colour Type IIa diamond, as well as the recovery of a 114 carat D colour Type IIa diamond in April.
The Letšeng mine is well-known for the production of large, top colour, exceptional white diamonds, making it the highest dollar per carat kimberlite diamond mine in the world.
Gem Diamonds has noted an improvement in the size and quality of diamonds recovered at Letšeng with the US$/carat trending positively.
“The market for Letšeng's high-quality diamonds has remained firm and this is anticipated to continue into H2, 2017,” comments Gem Diamonds CEO, Clifford Elphick.
“In addition, the revised life-of-mine plan was implemented during February, with the objective of reducing waste tons mined, improving near term cash flows. We expect to see the benefits emerge during 2017.”
Letšeng treated a total of 1.4 Mt of ore during the period, 75% of which was sourced from the main pipe, and 25% from the satellite pipe. The balance of the ore was treated through the alluvial ventures contractor plant, which was sourced from the main pipe and low grade stockpiles.
During Q1, 2017 engineering challenges were experienced at both of Gem Diamonds’ Letšeng plants that resulted in lower than planned plant availability. As a consequence, tons treated in the period were 76 000 tons lower than planned.
The temporary plant availability challenges are being addressed with the contracting partner, and full year guidance remains unaltered. The contribution from the satellite pipe is expected to meet the original target of 1.8 Mt for the full year.
Gem Diamonds reports that during the period, 25 479 carats were recovered at a grade of 1.53 cpht against an expected reserve grade of 1.61 cpht mainly due to the under performance of the main pipe contact material, which resulted in a mine call factor of 95%.
All images courtesy of Gem Diamonds
(Feature image: The 151.52 carat Type I yellow diamond recovered at Letšeng mine in Lesotho)