Ore Reserves are 82.3Mt as at
Mineral Resource Commentary
The Mineral Resource estimate factors in drilling and sampling completed by both MRL and a whollyowned subsidiary of BCI. The Mineral Resource estimate is based on the
Mineralisation within the
Drilling comprises reverse circulation ('RC') and diamond core holes. RC holes of approximately 140mm in diameter were completed using a standard face sampling hammer. HQ sized diamond holes were drilled as diamond tails after RC holes and PQ sized diamond holes were drilled as twins to RC holes. Drill holes were both vertical and inclined to be sub-perpendicular to the local strike and dip of the mineralisation.
BCI RC cuttings were taken at 1m and 2m intervals, with the 2m intervals being the predominant interval size. Samples were generated by sending dry drill cuttings through a cone splitter. Where the drill cuttings were wet and interpreted to be mineralised, these cuttings were left to dry in poly weave bags prior to being passed through a riffle 3 tier splitting process to generate dry samples. Wet un-mineralised samples were generated by either taking a grab sample from the drill cuttings or following the wet mineralised cuttings procedure. MRL RC samples were taken at 2m intervals, with all samples generated using a cone splitter. BCI and MRL samples were sent to laboratories in
Diamond core samples were taken at 1m, 2m, and 4m intervals, with 2m intervals being the predominant size for both. Complete core was sent to the laboratory for further preparation and XRF and TGA analysis or physical geo-metallurgical test work.
Geological interpretation was completed based on surface mapping, downhole geological logging, geophysics and geochemistry of RC and diamond core samples. Fe grade and key deleterious elements were estimated using ordinary kriging interpolation, while minor deleterious elements were estimated using inverse distance squared interpolation. A cut-off grade of 50% Fe was utilised.
Drilling was conducted on a 100m by 100m spacing (Indicated and Inferred classifications), with certain areas infilled to 50m by 50m (Measured and Indicated classifications), with a range of other criteria guiding the classifications within these drill spacing areas.
Ore Reserve Commentary
The Ore Reserve update is based on the
Current and planned mining is by conventional open pit methods. A conventional dry crushing and screening process produces direct shipping ore (DSO) lump and fines products transported by road train to Port Hedland and exported. Financial modelling of the operation is based on a CFR 62% Fe iron ore price of
Assumed mining factors included: dilution modelling by regularisation of the geological model using a selective mining unit of 12.5m by 12.5m by 5.0m, with the cut-off applied after regularisation; a 95% mining recovery factor and no minimum mining width.
Processing assumptions are based on the current conventional dry crushing and screening process in operation, producing DSO Lump and Fines products.
All required approvals are in place for the current ongoing operation.
The reported Ore Reserves are a subset of the reported Mineral Resources.
Contact:
Tel: +61 8 6311 3400
Email: brad.milne@bciminerals.com.au
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