Blackthorn Resources (ASX: BTR) final assay of 186 metres grading 2.25% copper from 221 metres adds to recent strong infill drilling results and should result in a resource upgrade in December for the Kitumba deposit at its wholly-owned Mumbwa Project in Zambia.
The final assay from KITDD_037 includes a higher grade intersection of 77 metres at 4.1% copper from 315 metres.
“We are pleased to provide the assay results for KITDD_037, which are the final set of assays required to begin the process of updating the April 2013 Mineral Resource Estimate,” acting chief executive officer Mike Oppenheimer said.
“We look forward to completing the updated Mineral Resource Estimate and expect to be able to report the results in December.”
Kitumba currently has a Resource of 108.9Mt at 1.09% copper at a 0.5% cut-off and an underground Probable Reserve of 33.5 million tonnes at 1.7% copper, or 541,000 tonnes of copper.
KITDD_037 was drilled to collect geotechnical information on the proposed sub-level block cave area, and as the hole traced through the western side of the high-grade zone the core was also sampled and assayed.
Phase 7 Drilling
Phase 7 drilling started in June 2013 with a focus on converting the Resource to the Measured category from the Indicated category.
Previous intercepts from the infill drilling had included 174 metres grading 5.04% copper from 240 metres and 243 metres at 5% copper from 208 metres.
Kitumba Copper Project
The company had earlier this month released the Pre-Feasibility Study for Kitumba that demonstrated its potential to be an economically and technically viable project.
Notably, work has begun on optimising the project with a focus on metallurgical recovery and mining sequence that could enhance economics.
This will be based on an updated Resource that incorporates recent high-grade drilling results, and is expected to lead to a PFS update in early 2014.
Kitumba is currently envisaged as an underground operation targeting the high-grade core of the deposit. This has a 11 year mine life based on 33 million tonnes of mineable ore with 572,000 tonnes of contained copper.
Blackthorn Resource’s upcoming Resource Estimation update will be central to optimising the Pre-Feasibility Study that should enhance project returns.
Given that it will include inputs from the Phase 7 infill drilling program that has returned results including 174 metres grading 5.04% copper from 240 metres and 243 metres at 5% copper from 208 metres, there is potential for a Resource growth and/or an increase in the Resource to higher confidence levels.
This is also expected to be reflected in the Ore Reserve.