Effective Grade
Reported Grade ÷ (1 + Dilution %)
A simplified dilution adjustment reduces the reported grade when additional lower-grade or waste material is assumed.
Deposit Calculator
Deposit Value Estimator
Estimate contained material, recoverable material, payable material, and a rough gross reference value using deposit tonnage, grade, dilution, recovery, payable percentage, and a value per unit.
Start Estimating
Enter Deposit Data
Estimate Deposit Value
Enter the metal or mineral being evaluated.
%
Additional lower-grade or waste material assumed to reduce
the effective grade.
%
Estimated percentage of contained material recovered.
%
Percentage of recovered material assumed to be payable.
$
Enter your own reference value. This is not a live commodity quote.
Estimated Results
Copper Deposit Estimate
Based on the figures entered into the estimator.
Effective Grade
—
After the entered dilution assumption.
Theoretical Contained Resource
—
Before recovery losses.
Estimated Recoverable Resource
—
Using the entered recovery assumption.
Estimated Payable Resource
—
After the entered payable percentage.
Gross Reference Value
—
Based on payable material and the reference value entered.
Gross Reference Value per Tonne of Ore
—
Reference value divided by the entered deposit quantity.
This is not a mine valuation.
The result does not subtract mining, processing, transportation,
capital, operating, financing, environmental, tax, royalty,
permitting, infrastructure, marketing, or other project costs.
How It Works
The Calculation Behind the Estimator
The estimator adjusts the entered grade for dilution, calculates contained material, applies recovery and payable assumptions, and converts the final material quantity into the unit used for the entered reference value.
Contained & Recoverable Resource
Deposit Quantity × Effective Grade × Recovery %
The calculator first estimates theoretical contained material, then applies the entered recovery assumption.
Payable Reference Value
Recoverable Quantity × Payable % × Reference Value
Payable material is converted into the selected pricing unit before the entered reference value is applied.
Deposit Assumptions
Why Each Input Changes the Result
Deposit estimates can change substantially when grade, dilution, recovery, or payable assumptions change.
Grade
Higher average grade means more target material is theoretically contained in each tonne of mineralized material.
Dilution
Additional waste or lower-grade material can reduce the effective grade of material delivered for processing.
Recovery
Not all contained metal or mineral can necessarily be recovered during processing.
Payable %
A saleable product may not receive payment for every unit of material it physically contains.
Worked Example
1 Million Tonnes of Ore at 0.8% Copper
Consider a hypothetical copper deposit containing one million metric tonnes of mineralized material at an average reported grade of 0.8%.
With 5% dilution, the simplified effective grade falls below the original 0.8%. A 90% recovery assumption then reduces the amount considered recoverable, and a 95% payable assumption reduces the quantity used for the final reference-value calculation.
The result is useful for understanding the mathematics behind a headline deposit number, but it is not an estimate of the economic value of the project.
Copper Deposit Example
Deposit quantity
1,000,000 metric tonnes
Reported grade
0.8% copper
Dilution
5%
Effective grade
≈ 0.7619%
Theoretical contained copper
≈ 7,619 t
Recovery
90%
Recoverable copper
≈ 6,857 t
Payable percentage
95%
Purpose
Gross reference estimate only
Important Context
Deposit Value Is Only the Beginning
A large contained or gross reference value does not tell you whether the resource can become an economically viable mine.
01
Cutoff Grade
Not every tonne of mineralized material may qualify for inclusion in an economic mining plan.
02
Mining Recovery
Geological resource does not automatically translate into material delivered to the processing plant.
03
Metallurgy
Mineralogy and processing characteristics can substantially affect actual recoveries and product quality.
04
Capital Costs
Mines may require processing plants, roads, power, water systems, equipment, and other major infrastructure.
05
Operating Costs
Labor, energy, maintenance, processing, waste handling, and transportation affect project economics.
06
Taxes & Royalties
Government obligations, ownership arrangements, and royalties can reduce the amount ultimately retained by a project.
07
Permitting
Regulatory approvals, community considerations, land access, and environmental obligations can affect development.
08
Product Terms
Concentrate quality, impurities, refining charges, treatment charges, and product specifications can influence realized value.
09
Market Conditions
Actual realized prices can differ from the reference value entered into a simple calculator.
Use With Resource Profiles
Put the Deposit Estimate in Context
Resource profiles provide the geology, supply, processing, market structure, and real-world uses that a calculator alone cannot show.
Related Tools
Continue With Resource Calculations
Educational Use
This estimator provides simplified mathematical estimates from user-supplied inputs. Results should not be used as mineral reserve statements, feasibility studies, property valuations, securities analysis, investment advice, engineering conclusions, or financial projections.
Earth Value Index
Numbers Matter More When They Have Context
Use Earth Value Index resource profiles, tools, Resource Uses, country information, and market references together to understand what natural resources are worth and why they matter.