Variography → Kriging → Preliminary Confidence Screen → KCMI Handoff
Goal: Generate a quick, transparent resource-estimation insight from Assay composites.
Flow: Approved domain-tagged composites → Variography → Block model → OK estimate → IDW/NN diagnostics → Cross-validation → Preliminary confidence screen → Grade-tonnage → KCMI-style handoff.
Scope: Screening and handoff tool—not a replacement for mine-planning/geological modelling software or a Competent Person report.
Before reporting: Validate domain geometry, top-cut, anisotropy, density, cut-off, mining method, metallurgy, economic assumptions and RPE in specialist software.
Pre-render variography, block model, estimation, cross-val, swath, classification, grade-tonnage, 3D view & KCMI report. ~30-60s with progress indicator.
Following Assay? Inspect the received data here; no second upload is required. Standalone upload supports externally prepared composites with documented coordinates, units, support and domains. Import alone does not establish geological or QA/QC acceptance. Use Dashboard for the overview, then review Setup before estimation.
Click or drag & drop a CSV file here
Accepts composite CSV from Assay (Orebit Assay)
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CSV with a header row; column names match without case sensitivity. Estimation requires hole_id, from_m, to_m, midx, midy and midz; Variography also requires domain.
Export the Master CSV from Assay’s Domain stage after assigning domains to composite intervals.
| Field | Aliases (auto-detected) | Required? |
|---|---|---|
| hole_id | HoleID, BHID, DHID, HOLE, hole | ✓ |
| from_m | FROM, from, From, depth_from, comp_from | ✓ |
| to_m | TO, to, To, depth_to, comp_to | ✓ |
| midx, midy, midz | x, y, z, easting, northing, rl, elevation | ✓ (for 3D estimation) |
| domain | DOMAIN, zone, rock_type_code | ✓ (for variography) |
| au_gpt | AU, Au, au_ppm, gold | optional |
| cu_pct, pb_pct, zn_pct, fe_pct | Cu, Pb, Zn, Fe, copper, lead, zinc, iron | optional |
| density | density_t_m3, bd_tm3, bulk_density | optional (QA/QC) |
Use documented dry bulk density in t/m³ for tonnage. SG/specific gravity is dimensionless and is preserved as an auxiliary column; it is not automatically used as dry bulk density.
Restore the synthetic 350-hole nickel laterite intervals, with limonite/saprolite domains and missing grades preserved.
Select target element, domains to estimate, and declustering parameters. Review the defaults and change parameters when your geology requires it.
Experimental variogram + model fit per direction. Nugget ratio < 80% is considered healthy (Sinclair & Blackwell 2002).
Extent from data + block size XYZ. Rule of thumb: block size ≈ ¼–½ × nearest data spacing.
Three parallel methods: IDW (inverse distance weighted, p=2), Ordinary Kriging (variogram-based BLUE), NN (nearest neighbor for validation). Search ellipsoid default = 1.5× variogram range, widened for sparse drilling up to a 3× cap — see the radius/range ratio on the Estimation tab.
Leave-one-out validation. Target: R² > 0.4 for OK, slope ≈ 1.0, mean residual ≈ 0 (no global bias).
Spatial bias validation. Drillhole grade vs estimate per X/Y/Z slice. Similar trends = unbiased; divergent = re-tune variogram/search.
Preliminary computational screening based on kriging variance, neighbor count, and distance to nearest composite. Cross-validation slope is shown as a global validation diagnostic. This is not a final JORC/KCMI classification; geological continuity, SOR, domains, modifying factors, and Competent Person review remain required.
Tonnage & mean grade sensitivity vs cutoff. Primary output for economic study (Stage 04 Mining Studies).
Visualize blocks with color-coded grade + composite drillholes as lines. Filter by preliminary confidence screen or cutoff.
Handoff summary + variogram/validation evidence + preliminary confidence rationale. This is a KCMI-style working report, not a certified Mineral Resource statement.
Use this checklist before taking the estimate into specialist mining software.
This checklist records handoff readiness only. It does not certify a JORC/KCMI Mineral Resource.
Blank = all estimated blocks. Enter a comparison cutoff explicitly. The current grade-tonnage confidence filter also applies.
8-page PDF: cover, variogram, block model, grade estimation, swath validation, classification, cut-off sensitivity, and KCMI commentary.
Every estimation step applied this session (variography, block model, kriging, classification). Embedded in the PDF report so the reported numbers are always traceable.
First 10 rows of the block model / composite data that will be exported.
Audit trail of every download this session (max 20). Persists in browser localStorage.