Mineral Recovery Grade Percentage Calculator
For metallurgists and flotation plant operators who have three assay numbers in hand — feed, concentrate and tailings grade — and need a defensible recovery figure in seconds, before committing to a full mass balance. Applies the standard two-product formula R = 100 * c * (f - t) / (f * (c - t)) to quantify flotation circuit metallurgical performance.
Flotation Recovery Calculator
Enter all three grades
Results are a two-product estimate for preliminary estimation only and are not a substitute for review by a qualified or licensed engineer.
How to Use This Calculator
- Type the feed (head) assay grade in % metal into the "Feed grade, f" field.
- Type the concentrate assay grade in % metal into the "Concentrate grade, c" field.
- Type the tailings assay grade in % metal into the "Tailings grade, t" field.
- Read the recovery percentage in large type and check the substituted formula underneath to confirm the numbers you entered are the ones being used.
- If the "inconsistent assays" or "undefined" message appears, correct the field it names — recovery needs c > f > t and c ≠ t.
FAQ
Q: What is the formula for mineral recovery percentage from assay grades?
A: The standard two-product formula R = 100 * c * (f - t) / (f * (c - t)), where f is the feed grade, c the concentrate grade and t the tailings grade — the same expression this calculator evaluates live.
Q: Why does the calculator show 0 % recovery?
A: Because the feed grade and the tailings grade you entered are equal, so the (f − t) term in the numerator is zero: the two-product formula returns 0 % when the tailings assay matches the feed assay, i.e. no upgrading has occurred.
Q: Why does it say "undefined" instead of a recovery number?
A: The denominator f * (c - t) is zero — either the concentrate grade equals the tailings grade (c − t = 0) or the feed grade was entered as 0. Supply a concentrate grade that differs from the tailings grade and a feed grade above zero.
Q: Can I use this recovery figure as a full metallurgical balance?
A: No — it is a two-product estimate for preliminary estimation only and is not a substitute for review by a qualified or licensed engineer, who can account for stream sampling, assay error and circuit mass balance.