Ore Grade Conversion Tool Guide

You cannot directly convert % Cu to g/t Au because copper and gold are different elements with distinct atomic masses and economic contexts. This tool performs unit conversions within the same element (e.g., 0.5% Cu → 5,000 g/t Cu), not inter-element equivalency. Converting between elements requires metallurgical assumptions—like recovery, concentrate grade, or by-product credits—which fall outside unit conversion and into process economics. NI 43-101 and JORC explicitly prohibit treating dissimilar elements as interchangeable in resource reporting. Always report grades per element, and use economic models—not unit converters—for cross-element valuation.

Yes—mathematically, 1% = 10,000 g/t for any element, because both units express mass fraction: 1% = 1 g/100 g = 10,000 g/1,000,000 g = 10,000 g/t. This holds regardless of atomic weight, as it’s a simple dimensional conversion (1% ≡ 10⁴ ppm ≡ 10,000 g/t). However, industry practice sometimes reports precious metals exclusively in g/t (e.g., Au, Ag) and base metals in % (e.g., Cu, Ni) for readability—not due to physical differences. The Ore Grade Conversion Tool enforces this universal equivalence, ensuring consistency required under CRIRSCO-aligned codes like JORC 2012 and NI 43-101 Section 1.2.

It doesn’t—nor should it. Ore grade unit conversion is purely dimensional and independent of mineralogy. Whether copper occurs as chalcocite (Cu₂S) or malachite (Cu₂CO₃(OH)₂) affects metal recovery and payable grade, not the fundamental mass-based unit (e.g., % Cu). This tool converts reported assay values only. For economic assessment, you must apply mineral-specific recovery factors and smelter penalties after conversion—per CIM Definition Standards and NI 43-101’s requirement to disclose ‘reasonably expected recovery’ (Section 1.4). Never substitute unit conversion for metallurgical modeling.

Yes—as long as you use it strictly for unit conversion of assay-derived elemental grades. Both JORC Code (2012, Clause 17) and NI 43-101 (Section 1.2) mandate clear, consistent grade units and require disclosure of the element reported (e.g., ‘g/t Au’, not ‘g/t gold’). This tool ensures traceable, auditable conversions (e.g., 2.35% Cu → 23,500 g/t Cu) with four-decimal precision. However, compliance also demands transparent documentation of sampling methodology, QA/QC, and detection limits—none of which this tool addresses. Always pair its output with full technical reporting per regulatory appendices.

The tool includes Pt, Pd, Au, Ag, and Cu because these elements are commonly reported in g/t for exploration and resource estimation—especially in polymetallic deposits—and frequently require unit harmonization across datasets (e.g., legacy drill logs in % vs. modern assays in g/t). Fe and Zn are typically reported in % for iron ore and zinc deposits, but their inclusion was prioritized based on CRIRSCO reporting frequency and cross-jurisdictional comparability needs. That said, the underlying algorithm supports any element; future versions may expand options. For now, use %→g/t conversion manually for Fe (1% Fe = 10,000 g/t Fe) following the same principle.

Rounding during conversion can materially distort cutoff grade calculations and NPV—especially near breakeven thresholds. For example, rounding 0.9995% Cu to 1.00% (vs. exact 9,995 g/t) introduces a 5 g/t error that may misclassify marginal tonnes. This tool preserves four-decimal precision in outputs to minimize such bias. Industry best practice (per SME Guidelines and AusIMM’s ‘Resource Estimation Handbook’) recommends retaining at least one extra significant figure during intermediate conversions and applying final rounding only after economic modeling—including recovery, costs, and metal price sensitivity. Always audit round-trip conversions (% → g/t → %) to verify fidelity.

No—atomic weight is irrelevant for % ↔ g/t conversion. These are mass-per-mass units: 1% = 1 gram of element per 100 grams of rock = 10,000 grams per metric tonne (1,000,000 g). Atomic weight matters only when converting compound grades (e.g., % CuFeS₂) to elemental grades (% Cu), which requires stoichiometric calculation. This tool assumes input is already elemental grade—as required by JORC 2012 Clause 17.2 and NI 43-101 Section 1.2. If your assay reports mineral forms, perform stoichiometric conversion first using molecular weights, then use this tool for unit standardization.