JORC 2012 vs KCMI 2017 — What Indonesian Geologists Need to Know

If you’ve ever filed a resource statement for an Indonesian project, you’ve hit the question: do I report under JORC or KCMI? The honest answer is both, and the longer answer is the subject of this post.

JORC 2012 (Joint Ore Reserves Committee, Australasia) is the international standard most foreign investors expect. KCMI 2017 (Komite Cadangan Mineral Indonesia) is the domestic standard required for ESDM (Kementerian Energi dan Sumber Daya Mineral) reporting. They’re aligned in spirit — both descend from the same CRIRSCO template — but the details matter when you’re filing a feasibility study or a bankable report.

What both standards agree on

The core architecture is the same:

• Three resource categories: Inferred → Indicated → Measured (increasing geological confidence)
• Two reserve categories: Probable → Proved (corresponds to Indicated/Measured + modifying factors)
• Competent Person signs off (different name, same concept — “Qualified Person” in NI 43-101)
• Reasonable Prospects for Eventual Economic Extraction (RPEEE) — you can’t report a resource that has no realistic path to mining
• Table 1 disclosure framework — explicit list of items that must be addressed

If your data validation, geological model, and estimation methodology are sound, the report content is 90% the same regardless of which standard you cite.

Where they actually differ

1. Competent Person qualifications

JORC 2012: minimum 5 years of relevant experience in the style of mineralization being reported, member of a Recognised Professional Organization (RPO) — most commonly AusIMM, AIG, or equivalent.

KCMI 2017: must be registered as Competent Person Indonesia (CPI) under PERHAPI (Perhimpunan Ahli Pertambangan Indonesia) or IAGI (Ikatan Ahli Geologi Indonesia). Foreign CPs can sign off but typically need a co-signing Indonesian CP for ESDM submissions.

Practical implication: if your project is Indonesian-owned and reporting domestically, you need a CPI on the report. If you’re reporting to a foreign exchange (ASX, TSX), the JORC/NI 43-101 CP is what matters. Many bankable studies use both.

2. Reporting threshold and scope

JORC 2012: applied to public reports, defined as “reports prepared for the purpose of informing investors or potential investors.” Internal company reports aren’t required to be JORC-compliant, but most majors apply it anyway as a quality standard.

KCMI 2017: applied to all publicly disclosed reports of mineral resources and reserves in Indonesia, including feasibility studies submitted to ESDM and IUP holders’ annual reports.

Practical implication: ESDM submissions = KCMI-mandatory. ASX/TSX listings = JORC/NI 43-101 mandatory. Dual-listed projects need both.

3. Exploration Results disclosure

JORC: Section 1 (Sampling Techniques and Data) and Section 2 (Reporting of Exploration Results) cover this.

KCMI: equivalent sections, but KCMI explicitly requires disclosure in Bahasa Indonesia for the executive summary and material assumptions.

Practical implication: budget for translation. A bilingual report is the norm.

4. Data validation and QA/QC

Both require disclosure of:

• Sampling protocols
• QA/QC samples (blanks, standards, duplicates) and their results
• Laboratory certifications
• Any data adjustments (top-cuts, cap values, exclusions)

JORC is slightly more prescriptive about quantifying QA/QC performance (e.g., “describe the level of mineral resource estimate confidence and its limitations”).

KCMI is essentially identical here — both descended from CRIRSCO template.

5. Modifying Factors for Reserves

For converting Resource → Reserve, both require demonstration of:

• Mining method
• Metallurgical recovery
• Infrastructure availability
• Permits and licensing
• Marketing
• Environmental and social

KCMI specifically requires reference to Indonesian permits — IUP (Izin Usaha Pertambangan), IUPK, AMDAL (environmental impact assessment).

The compliance checklist

For an Indonesian project that needs to satisfy both standards, here’s what I check before sign-off:

Data layer

• All drillhole data validated (collar, survey, assay, geology) — see drillhole validation post
• QA/QC samples (blanks, standards, duplicates) ≥ 5% of total samples
• Laboratory certificate copies attached
• BDL convention documented
• Top-cut rationale disclosed (if applied)

Geological model

• Domain boundaries justified (lithology, structure, weathering)
• Domain separation tested (ANOVA or equivalent)
• Section/plan views included for review

Estimation

• Variogram parameters disclosed (range, sill, nugget, model type)
• Search parameters disclosed (search ellipsoid, min/max samples, octant restrictions)
• Estimation method justified (kriging vs IDW vs nearest neighbor)
• Block model parameters disclosed (cell size, parent block, sub-blocking)
• Cross-validation or swath plot validation included

Classification

• Measured/Indicated/Inferred criteria defined (drill spacing, kriging variance, etc.)
• Classification justified relative to geological continuity
• Classification map or table included

Reporting

• JORC Table 1 Section 1-4 completed (or KCMI equivalent)
• Bahasa Indonesia executive summary (for KCMI)
• Competent Person consent letter signed
• CP qualifications and experience disclosed
• Material assumptions, limitations, and risks listed
• Reasonable Prospects for Eventual Economic Extraction demonstrated

Modifying factors (for Reserves)

• Mining method and dilution/recovery factors
• Metallurgical test work
• Permits status (IUP, AMDAL, IUPK as applicable)
• Infrastructure assessment
• Economic assumptions (commodity price, cost, FX)

Common pitfalls

In reviews I’ve seen, these are the recurring failures:

1. No JORC Table 1 section — the report has all the content scattered across narrative, but no structured Table 1 disclosure. Fix: use the Table 1 template explicitly, even if it’s repetitive.

2. Top-cut applied but not disclosed — analyst capped at P98 but didn’t say so. Auditor finds it in the workings. Bad look. Fix: always disclose top-cuts in the assay validation section.

3. Undisclosed exclusions — “we removed two outlier holes from the estimate” with no rationale. Even if the rationale is solid, omitting it is a JORC concern. Fix: list every exclusion with reason.

4. Variogram parameters absent — the estimation section says “ordinary kriging” without disclosing variogram model, range, or sill. Reviewer can’t replicate. Fix: include the variogram parameters table.

5. No CP consent letter — surprisingly common in early-stage filings. Fix: get the consent letter signed and filed before publication, not after.

Tools that help

The Geologist Toolkit phases generate JORC/KCMI-aligned outputs by design:

• Phase 01 (Drillhole Prep): produces JORC Table 1 Section 1 (Sampling Techniques and Data) — collar/survey/assay validation logs, QA/QC summary, raw-to-clean trail.
• Phase 02 (Drilling EDA): produces top-cut rationale, BDL handling, domain separation tests (ANOVA + boxplots), composite generation logs.
• Phase 03 (Resource Estimation): produces variogram parameters table, search parameter disclosure, kriging validation (cross-validation, swath plots), and a JORC Table 1 Section 3 template.

All output is deterministic and exportable as PDF + CSV. Attach directly to your Table 1.

See the toolkit → · Buy on Lynk.id →

Bottom line

JORC and KCMI aren’t competing standards — they’re regional implementations of the same idea: transparent, defensible, reproducible resource reporting. If your data validation is sound, your methodology is documented, and your CP is properly qualified, you can report under both with the same body of work and a few section changes.

Pick the one your audience requires. Apply the discipline of the stricter one. Sign with confidence.

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Working on a JORC or KCMI report and stuck on a specific section? Email hello@orebit.id — happy to share examples.

# From this article:
open geotools.orebit.id
load(your_drillhole.csv)
apply(workflow_above)

# Done. Ship the report.