Star Diamond Corp announced that a total A total of 2,409 diamonds weighing 123.27 carats have to date been recovered from the second bulk sample trench (19FALCT004) excavated on its Star kimberlite at the Fort à la Corne kimberlite field in central Saskatchewan.
These initial results are from the second of 10 bulk sample trenches excavated by 60% optionee Rio Tinto Exploration Canada Inc in 2019.
The average diamond grades from the first two trenches are similar to historical diamond grade results detected from the underground bulk sampling and large diameter drilling completed on the Star kimberlite between 2004 and 2009. These results are also similar to the overall weighted average grade 14 carats per hundred tonnes reported in Star Diamond’s PEA of the Star and Orion South kimberlites .
The three largest diamonds recovered to date from 19FALCT004 are 2.98, 2.03 and 1.99 carats, respectively, and were all recovered from Early Joli Fou kimberlite. The EJF is the dominant kimberlite unit within the project in terms of ore volume and diamond grade.
As disclosed by Star Diamond on August 4, 2020, there are indications that recent diamond breakage has occurred in the diamond parcels recovered thus far from RTEC’s trench cutter bulk sampling program, suggesting that the extraction and/or processing systems being used by RTEC may be resulting in diamond breakage. Comprehensive diamond breakage studies are required to assess the nature and extent of the diamond breakage resulting from RTEC’s methods and the possibility that larger diamonds would have been recovered absent such breakage.
Senior vice president of exploration and development, George Read, states: “The initial diamond results from 19FALCT004 and 19FALCT001 continue to show grades similar to the previous underground bulk sampling and LDD performed by Star Diamond on the Star kimberlite. Individual EJF kimberlite samples recovered in the first two trenches exhibit a range of grades 9.81 to 21.22 cpht for 19FALCT004 and 4.88 to 23.34 cpht for 19FALCT001, which are as expected for the EJF kimberlite.”
Source: DCLA