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Mine Dilution and Ore Loss Calculator

Mine dilution and ore loss are distinct mining modifying factors. Dilution is material below the cut-off grade or value that is intentionally or inadvertently mined with ore. It can increase the final mined mass and change the blended grade. Mining loss is ore-grade material within the mine design that is not extracted. Mining recovery is the complement used here: recovered ore equals in-situ ore multiplied by the mining-recovery fraction. Mining recovery is not metallurgical or process recovery. GeoMiner applies the operations in a visible order. First, it multiplies in-situ ore tonnage by mining recovery to calculate recovered ore and subtracts that quantity from in-situ ore to expose ore loss. Second, it calculates added diluent from one of two explicitly selected percentage definitions. Third, it blends recovered ore and diluent by mass. Diluted grade equals recovered ore multiplied by in-situ ore grade plus diluent multiplied by diluent grade, divided by final mined material. The result reports recovered ore, ore loss, added diluent, final mined material, both dilution percentages, mass-weighted diluted grade, normalized parts per million, and percentage change from the input grade. The tool supports metric tonnes or U.S. short tons, provided every tonnage uses the same unit. Grade can be entered as parts per billion, parts per million, percent by mass, grams per metric tonne, milligrams per kilogram, kilograms per metric tonne, or troy ounces per U.S. short ton. Ore and diluent grades must use the same selected grade unit. The arithmetic is mass-ratio based, so it does not convert or mix metric tonnes and short tons inside one scenario. The word dilution does not identify a denominator. On an added-to-recovered-ore basis, dilution percent equals diluent mass divided by recovered ore mass. Ten percent on this basis adds ten mass units of diluent to every one hundred mass units of recovered ore. The diluent is then about 9.09 percent of the final one-hundred-and-ten-unit blend. On a final-mined-material basis, dilution percent equals diluent mass divided by final blended mass. Ten percent on this basis means ten of every one hundred final mass units are diluent and ninety are recovered ore. The equivalent added-to-ore factor is about 11.11 percent. Both conventions can be valid when properly defined. They are not interchangeable. Preserve the exact equat

Verification resources

Cross-check terminology, classification, methods, and safety with these authoritative external resources.

  • undefined. Defines dilution and mining losses as mine-specific modifying factors, distinguishes planned and unplanned dilution, and requires both diluted grade and recovered material to be supported and documented.
  • undefined. A current filed example that distinguishes in-situ resources from mine-planning assumptions and applies explicit zero-grade dilution and ore-loss factors to reserve work.
  • undefined. Publishes an added-to-ore dilution convention in which reserve tonnes equal recovered block tonnes multiplied by one plus the dilution factor.
  • undefined. Publishes a final-material weighted-grade relationship that includes the measured grade of diluting material instead of silently assuming barren waste.

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Common questions

What is mine dilution?
Dilution is below-cut-off or non-ore material that is intentionally or inadvertently mined with ore. It usually adds mined mass and changes the blended grade, but its origin, grade, timing, and definition must be documented.
Why can a 10 percent dilution input produce two percentages?
A percentage based on diluent divided by recovered ore is not the same as diluent divided by final mined material. Ten percent added to ore equals about 9.09 percent of the final blend; ten percent of the final blend equals about 11.11 percent added to ore.
How does this calculator apply ore loss?
It first multiplies in-situ ore tonnes by mining recovery to obtain recovered ore. It assumes the recovered ore keeps the entered in-situ grade, then adds diluent and calculates a mass-weighted blended grade. Selective or grade-dependent losses are outside this model.
Is mining recovery the same as plant recovery?
No. Mining recovery describes ore-grade material extracted from the mine design. Metallurgical or process recovery describes metal recovered from plant feed. This tool includes mining recovery only.
Can this calculator establish a Mineral Reserve?
No. A reserve requires supported mine design, modifying factors, economics, scheduling, classification, applicable reporting standards, multidisciplinary work, and qualified professional judgment. This page performs one transparent arithmetic scenario only.

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