Caledonia Mining Corp PLC (LON:CMCL, NYSE:CMCL) announced an increase in reserves and resources at its 64%-owned Blanket gold mine in Zimbabwe.
Proven and probable reserves increased 1% to 528,000 ounces (or 17% including depletion of 84,925 ounces since the last update in July 2018) and measured and indicated (M&I) resources rose 12% to 902,000 ounces (or a 23% increase including depletion).
“Today's announcement marks an additional milestone in the long track record of growing mineral resources and successfully converting inferred mineral resources into M&I to keep extending the life of mine at Blanket since its inception in 1906,” said chief executive Steve Curtis.
Inferred resources at Blanket decreased 10% from July 2018 to 866,000 ounces as at January 1, 2020.
“The reduction in inferred mineral resources is due partly to successful conversion to M&I, at approximately 18 per cent, and partly the lack of deep level exploration over the last 12 months, awaiting the development of new drilling platforms on the lower levels via the recently-commissioned Central Shaft,” said Curtis.
“The latest geological information available, combined with a lower mineral resource cut-off grade, from 2.1 grammes per tonne (g/t) to 1.5 g/t, due to the higher gold price, added lower grade mineral resources, resulting in a reduction in the inferred mineral resources grade.
“The lower inferred mineral resources grade is broadly consistent with Blanket's recently achieved grade, which demonstrates that Blanket can comfortably mine at this grade,” he added.
Total measured and indicated resources now stand at 8.5mln tonnes at a grade of 3.29 g/t, a 12% reduction in grade although the updated resource grade remains consistent with current Blanket run of mine grade.
The reserve grade of 3.38 g/t remained unchanged from July 2018 with the cut-off grade also remaining unchanged at 2.1 g/t.
"Now that the Central Shaft is completed, we will have the ability to do more deep level exploration and we expect to replace the depleted mineral resources as we continue to go deeper, extending the life of mine while achieving the 80,000-ounce target from 2022 onwards," Curtis concluded.
Blanket's mineral resources have grown about 86% since 2011 despite mining over 400,000 ounces over this period.