Star Diamond Corp. [DIAM-TSX] has recovered a total of 2,755 diamonds weighing 178.98 carats to date from the seventh (19FALCT005) bulk sample trench excavated on the Star kimberlite by Rio Tinto Exploration Canada Inc. in 2019. The corporation’s Fort à la Corne kimberlites (including the Star/Orion South diamond project) are located in central Saskatchewan.
“We are pleased by the recovery of two larger 16.96- and 6.35-carat D-colour Type IIa diamonds from Rio Tinto Canada’s seventh trench,” said Ken MacNeill, President and CEO. “Star Diamond’s own underground bulk sampling and large-diameter drilling programs conducted between 2004 and 2009 previously recovered diamonds as large as 49.5 and 45.9 carats from the Star and Orion South kimberlites, respectively. We have been disappointed by Rio Tinto Canada’s failure to date to recover larger diamonds, which we believe is a consequence of its unproven and inadequately tested extraction and/or diamond recovery methodologies causing undue diamond breakage. Nevertheless, the diamonds recovered from the seventh trench continue to highlight the excellent potential for the recovery of large high-value diamonds from the Star kimberlite.”
MacNeill added, “We are also pleased that the initial results from the first seven reported trenches continue to validate the grades outlined in our preliminary economic analysis that was based upon Star Diamond’s own prior underground bulk sampling and large-diameter drilling programs.”
Senior technical adviser George Read stated: “The seventh trench (19FALCT005) has produced a total of 15 diamonds ranging from 1.10 carats to 16.96 carats. The six largest diamonds recovered to date from 19FALCT005 are 16.96, 8.05, 6.35, 3.72, 3.53 and 3.29 carats, respectively, and were all recovered from Early Joli Fou (EJF) kimberlite. The EJF is the dominant kimberlite unit within the project in terms of ore volume and diamond grade. The 16.96- and 6.35-carat diamonds have been confirmed as being Type IIa using Fourier transform infrared spectrometry and their colour has also been confirmed as D. The recovery of these high-colour, Type IIa diamonds in this bulk sample strengthens the expectation for recovery of large, high-value diamonds in a future producing diamond mine. It is important to also note that the three large diamonds included in these trench results were all recovered from a soft EJF kimberlite breccia unit, from which kimberlite would have been more easily extracted with minimal mechanical attrition.”