Breakeven Stripping Ratio
Estimate breakeven waste/ore mass ratio from recovered revenue and incremental costs; negative margins are retained, not converted into feasible stripping plans.
Description
A breakeven stripping ratio allocates the ore margin remaining after mining and processing to waste removal.
A breakeven stripping ratio allocates the ore margin remaining after mining and processing to waste removal. Negative ore margin produces a negative ratio under this algebra.
The tool returns breakevenWasteOreMassRatio (breakeven waste ore mass ratio); preStrippingMarginPerOreTonne (pre stripping margin per ore tonne); economicPositiveMargin (economic positive margin). Input measurements and model parameters are supplied by the caller; the tool computes the stated summary rather than acquiring those measurements.
When to use Breakeven Stripping Ratio
Use Breakeven Stripping Ratio when you already have recoveredRevenuePerOreTonne, oreMiningCostPerTonne, processingCostPerOreTonne, wasteCostPerTonne and want breakevenWasteOreMassRatio, preStrippingMarginPerOreTonne, economicPositiveMargin. This is useful for checking a supplied calculation, documenting a measurement convention, or comparing observations prepared on the same basis.
How to use Breakeven Stripping Ratio and understand its results
- Enter recoveredRevenuePerOreTonne, oreMiningCostPerTonne, processingCostPerOreTonne, wasteCostPerTonne using the field table below. Match the units, ordering and data boundaries described in the calculation.
- Run the tool after checking the stated bounds and matching paired observations or categories. A malformed request gives a tool error rather than a usable measurement.
- Read breakevenWasteOreMassRatio, preStrippingMarginPerOreTonne, economicPositiveMargin. Use the calculation and interpretation below to distinguish amounts, ratios, signs and decision flags where applicable.
- Review the supplied parameters and assumptions before using the result in a report or comparing it with another observation.
| Input field | Meaning | Value type and bounds | Requirement |
|---|---|---|---|
| recoveredRevenuePerOreTonne | Recovered revenue per ore tonne | number | Required |
| oreMiningCostPerTonne | Ore mining cost per tonne | number | Required |
| processingCostPerOreTonne | Processing cost per ore tonne | number | Required |
| wasteCostPerTonne | Waste cost per tonne | number | Required |
Use consistent currency per tonne, nonnegative revenue and ore costs, and positive waste cost. Return signed margin, signed ratio and a positive-margin boolean.
breakeven ratio = (recoveredRevenue−oreMiningCost−processingCost)/wasteCost The symbols refer to the supplied quantities or generated values described above; unit conversions and comparison boundaries follow the stated implementation.
{
"input": {
"recoveredRevenuePerOreTonne": 100,
"oreMiningCostPerTonne": 20,
"processingCostPerOreTonne": 30,
"wasteCostPerTonne": 10
},
"output": {
"breakevenWasteOreMassRatio": 5,
"preStrippingMarginPerOreTonne": 50,
"economicPositiveMargin": true
}
}Limitations and assumptions
Discounting, capital, royalties and other costs are excluded unless included in supplied terms. A negative ratio is not a feasible stripping allowance.
Numerical inputs must be finite. The tool checks its declared input shape and calculation constraints; those checks do not verify the quality, calibration or representativeness of the supplied observations.
Alternative or Complementary methods
Ultimate Pit Stripping Ratio: Compare cumulative/incremental stripping across nested shells; limits do not solve ultimate-pit optimization or establish slope feasibility. Stripping Schedule: Apply prestripped waste credit sequentially to fixed ore/stripping schedule and screen capacities; does not optimize precedences or silently reschedule.
Methodological background: Surface Mining Technology: stripping ratios and pit layouts.1
References
-
Surface Mining Technology: stripping ratios and pit layouts — NPTEL, Indian Institute of Technology Kharagpur
Similar or alternative tools
- Ultimate Pit Stripping Ratio
Compare cumulative/incremental stripping across nested shells; limits do not solve ultimate-pit optimization or establish slope feasibility.
- Stripping Schedule
Apply prestripped waste credit sequentially to fixed ore/stripping schedule and screen capacities; does not optimize precedences or silently reschedule.