Ore Grade Calculator

Work out ore grade instantly with clear inputs, formula shown and shareable results.

About Ore Grade Calculator

Ore grade is contained metal as a percentage of ore mass, or grams per tonne for precious metals where 1% equals 10,000 g/t. What matters commercially is recoverable value per tonne — grade times price times metallurgical recovery — because that is what must cover mining and processing cost.

Formulas

Ore grade

Grade % = contained metal x 100 / ore tonnage; g/t = grade % x 10,000

Recoverable value

Value per tonne = grade x recovery x metal price

Worked example

With the default values below, Ore Grade Calculator returns Ore Grade of 1.5000%. Change any input above and every figure here is recalculated in your browser.

Inputs used

Metal Containedminimum 0 tonnes: 15 tonnes
Ore Tonnageminimum 0 tonnes: 1,000 tonnes
Metal Priceminimum 0 per tonne: 8,500 per tonne
Metallurgical Recoveryaccepts 0.01–100 %: 88 %

Results

Ore Grade: 1.5000%
Recoverable Metal: 13.200
Recoverable Value Per Tonne Of Ore: $112.20
Grade In Grams Per Tonne: 15,000.0

Step by step

1Values used
2Ore grade
3Recoverable value
4Ore Grade= 1.5000
5Recoverable Metal= 13.200
6Recoverable Value Per Tonne Of Ore= 112.20
7Grade In Grams Per Tonne= 15,000.0

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Why quote grade in different units?

Convention follows value density: percent for base metals such as copper and zinc, grams per tonne for gold and platinum, and parts per million or ounces per ton in some jurisdictions. Always state the unit.

What grade is economic?

Entirely dependent on metal price, depth, recovery and scale. Open-pit copper at 0.3% can be economic at large scale while underground gold below 3 g/t often is not.