A mine plan may identify material with favourable characteristics that cannot all be extracted or delivered as intended. Some can be left behind, misclassified or lost during the operating sequence. The owner's decision is how to estimate and control these losses without confusing them with dilution or with metallurgical recovery inside the plant.
State where the loss occurs
A technical account should identify the stage and mechanism under discussion. Material remaining in the excavation, material sent to another destination and valuable constituents lost during processing describe different problems. Combining them into one recovery percentage makes responsibility difficult to assign. CIM's mine-planning guidance addresses mining recovery and ore loss within the engineering case. The owner should ask whether the estimate is based on the proposed method, relevant observations or a provisional allowance. Its confidence and limitations should be explicit wherever it enters the schedule and the associated economic calculations used for decisions.
Examine boundaries that are difficult to operate
A hypothetical extraction plan may require leaving material beside an access route or within a shape that equipment cannot safely recover. Geological uncertainty can also affect classification. The mining team should explain which conditions drive the expected loss and how design alternatives change it. The objective is not to promise total recovery. It is to compare practical options while preserving the associated costs, safety requirements and schedule consequences. A more aggressive extraction assumption should have evidence showing that the proposed operation can achieve it within the chosen design and operating controls.
Track destination as well as excavation
Material movement records should support reconciliation between the model, the excavation and the destination. A parcel physically removed may still fail to reach the intended stockpile or plant stream. Survey, classification and dispatch controls therefore belong in the operating design. The appropriate method depends on the project and should be developed by the responsible specialists. JORC's wider framework reinforces the need for a coherent mining and processing case. Investors should see how the proposed controls address the modelled loss mechanisms rather than accept a general assurance that modern equipment will achieve a favourable recovery.
Make differences lead to investigation
Once operating evidence exists, reconciliation should compare like quantities over compatible periods. A difference can arise from measurement uncertainty, model limitations or operating performance. The response should investigate causes before assigning blame or changing the assumption. Owners can prepare that process during development, including responsibility for records and review. Investors can test the financial sensitivity to a less favourable outcome without presenting it as an observed result. Keeping ore loss in its own account allows management to choose a targeted corrective action and helps prevent an unexplained shortfall from being carried forward inside an apparently stable production forecast.
