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Pit Optimisation Revenue Estimator

The Pit Optimisation Revenue Estimator gives a rough block-economics picture for a gold-style deposit — recoverable ounces, gross revenue, total cost and net margin — from tonnage, grade, recovery, metal price and cost per tonne.

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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 ore tonnes, grade in grams per tonne, and metallurgical recovery as a percentage.
  2. Enter the metal price per troy ounce and the combined mining + processing cost per tonne.
  3. Read recoverable ounces, gross revenue, total cost and net margin.

How it works

Recoverable metal (oz) = ore tonnes × grade (g/t) × recovery% ÷ 31.1035 g/oz. Gross revenue = recoverable oz × metal price per oz. Total cost = ore tonnes × cost per tonne. Net margin = gross revenue − total cost. 31.1035 g is one troy ounce.

Worked example

Worked example. 1,000,000 t at 1.5 g/t with 90 % recovery yields 43,403.48 oz. At $2,500/oz that is $108,508,688.73 gross revenue; at $40/t total cost is $40,000,000.00, leaving a $68,508,688.73 net margin.

Common mistakes

  • Using grams per tonne with a price per gram, or vice versa — grade must be g/t and price must be per troy ounce.
  • Entering recovery as a fraction (0.9) instead of a percentage (90).
  • Treating the net margin as profit; it excludes selling, refining, royalties, capital and sustaining costs.

Frequently asked questions

Is this real pit optimisation?

No. Proper optimisation (e.g. Lerchs–Grossmann) uses a block model, revenue factors and geotechnical constraints to build the pit shell. This is a fast single-block estimate for scoping.

Why divide by 31.1035?

Precious-metal grades are in grams per tonne but metal is priced per troy ounce, and one troy ounce is 31.1035 grams, so the division converts grams of recovered metal to ounces.

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

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