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Mining Recovery & Dilution Impact Calculator

See how mining recovery and dilution reshape what actually reaches the mill. Starting from your in-situ ore block, it recovers the mineable fraction, adds waste dilution to give run-of-mine (ROM) tonnes, dilutes the head grade, and shows the contained metal you deliver.

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How to use this calculator

Enter Values

Enter your values and press Calculate to see results.

Before you rely on this: First-pass guide only. Verify safety-critical or regulated work against the relevant standards, your project requirements and a qualified professional.

How to use this calculator

  1. Enter the in-situ ore tonnes and in-situ grade for the block or reserve you are assessing.
  2. Enter your mining recovery (0-100%) and the dilution you expect from over-break and waste pick-up.
  3. Read the recovered ore, diluted ROM tonnes, diluted grade and delivered contained metal, then flex recovery and dilution to test the trade-off.

How it works

Recovered ore = in-situ tonnes x recovery / 100. Diluted ROM tonnes = recovered ore x (1 + dilution/100). Assuming waste dilution carries zero grade, diluted grade = in-situ grade / (1 + dilution/100), which keeps contained metal equal to recovered ore x in-situ grade / 100. Dilution therefore adds tonnes and drops head grade without adding metal.

Worked example

Worked example. For 100,000 t at 2% grade with 95% recovery and 10% dilution: recovered ore = 95,000 t, diluted ROM = 104,500 t, diluted grade = 1.82%, and delivered contained metal = 1,900 t.

Common mistakes

  • Confusing mining recovery (how much ore you actually extract) with mill/metallurgical recovery, which is applied later.
  • Assuming dilution destroys metal — with zero-grade waste the metal is preserved; it is the grade and processing cost per tonne that suffer.
  • Entering recovery or dilution as a fraction (0.95) instead of a percentage (95).

Frequently asked questions

Does this include mill recovery?

No. It stops at the ROM/delivered-to-mill point. Multiply the delivered contained metal by your metallurgical recovery to estimate recovered product.

What if diluting material actually carries some grade?

This tool assumes zero-grade dilution, which is the conservative and most common planning case. If waste carries grade, the true diluted grade will be slightly higher than shown.

Related tools

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Tip: Enter any known values to calculate the remaining results.

All calculations run in your browser. Your inputs are never saved or transmitted.