Floating Cone Value

Evaluate incremental value of a predefined floating cone excluding mined blocks; does not construct cone geometry or optimize pits.

Description

A floating-cone calculation evaluates the value of a predefined group of pit blocks.

A floating-cone calculation evaluates the value of a predefined group of pit blocks. Already mined blocks do not contribute to the incremental value of extracting that group now.^[1]

The tool returns incrementalConeValue, includedUnminedBlockIndexes, positiveIncrementalCone. The computation uses supplied observations and parameters rather than acquiring measurements.

When to use Floating Cone Value

Use this for the following task: Evaluate incremental value of a predefined floating cone excluding mined blocks; does not construct cone geometry or optimize pits. Prepare observations and calibration parameters on the same unit and reporting basis.

How to use Floating Cone Value and understand its results

Prepare the measured quantities and supplied model parameters. Match the units and align paired lists before calculating.
Enter blockValues, coneBlockIndexes, alreadyMinedBlockIndexes according to the field table, then run the tool.
Read incrementalConeValue, includedUnminedBlockIndexes, positiveIncrementalCone. Use the calculation below to interpret the selected mean or the model’s signs, units and comparison flags.
Review the supplied assumptions and calibration before comparing or reporting the result.

Input field	Meaning	Value type and bounds	Requirement
blockValues	Block values	list of number	Required
coneBlockIndexes	Cone block indexes	list of number	Required
alreadyMinedBlockIndexes	Already mined block indexes	list of number	Required

Provide a nonempty block-value list and cone index list. Both index lists must contain unique valid zero-based positions; remove mined positions while retaining cone order.

incremental value = ΣblockValue[i] for cone indexes not already mined; positive = value>0

The symbols and boundary conditions refer to the supplied fields and the implementation described above.

Output field	Meaning	Value type
incrementalConeValue	Incremental cone value	number
includedUnminedBlockIndexes	Included unmined block indexes	list of number
positiveIncrementalCone	Positive incremental cone	boolean

json

{
  "input": {
    "blockValues": [
      100,
      -20,
      -30,
      40
    ],
    "coneBlockIndexes": [
      0,
      1,
      2
    ],
    "alreadyMinedBlockIndexes": [
      1
    ]
  },
  "output": {
    "incrementalConeValue": 70,
    "includedUnminedBlockIndexes": [
      0,
      2
    ],
    "positiveIncrementalCone": true
  }
}

Limitations and assumptions

Negative block values are permitted, and an empty remaining cone has value zero. The tool does not construct cone geometry, enforce precedence or optimize a pit.

Numerical inputs must be finite. Input-shape and calculation checks do not establish measurement quality or the validity of a supplied calibration.

Alternative or Complementary methods

Choose Lerchs-Grossmann Weight when you need its operation: Calculate economic node weights for process/waste blocks; prepares weights but does not execute Lerchs–Grossmann closure or precedence slopes. Choose Cut-Off Grade for the complementary operation: Derive a mass-fraction cut-off grade from caller cost, realized metal price and recovery; excludes capacity constraints, taxes and multi-metal credits.

Background reference: Surface Mining Technology: stripping ratios and pit layouts.

References

Surface Mining Technology: stripping ratios and pit layouts — NPTEL, Indian Institute of Technology Kharagpur

Similar or alternative tools

Lerchs-Grossmann Weight
Calculate economic node weights for process/waste blocks; prepares weights but does not execute Lerchs–Grossmann closure or precedence slopes.
Cut-Off Grade
Derive a mass-fraction cut-off grade from caller cost, realized metal price and recovery; excludes capacity constraints, taxes and multi-metal credits.