Escondida (Minera Escondida Ltda)
Technical Report Summary – Minera Escondida Limitada
Identity and ownership
- Operator
- Minera Escondida Ltda (MEL), BHP-operatedhighEscondida TRS (S-K 1300) — as of 2022-06-30
- Jurisdiction
- Chile — Antofagasta Region (~170 km SE of Antofagasta, ~3,100 m elevation)highEscondida TRS (S-K 1300) — as of 2022-06-30
- Primary commodity
- CopperhighEscondida TRS (S-K 1300) — as of 2022-06-30
- Deposit type
- Supergene-enriched porphyry copper; monzonite-granodiorite intrusions; three zones — secondary oxide, supergene sulphide, hypogene sulphidehighEscondida TRS (S-K 1300) — as of 2022-06-30
- First production
- 1990highWikipedia — Escondida (fallback source; well-established) — as of 1990
- Years in operation
- 36derived from first production year
Disclosed interests
- Interest 1
- BHP Group Limited — 57.5%highEscondida TRS (S-K 1300) — as of 2022-06-30
- Interest 2
- Rio Tinto — 30%highEscondida TRS (S-K 1300) — as of 2022-06-30
- Interest 3
- JECO Corporation — 10% (Mitsubishi-led consortium)highEscondida TRS (S-K 1300) — as of 2022-06-30
- Interest 4
- JECO 2 Limited — 2.5%highEscondida TRS (S-K 1300) — as of 2022-06-30
- Interest 5
- Mitsubishi Corporation — 8.25% (attributable, via the JECO Corporation / JECO 2 Limited consortium)highMitsubishi Corporation Mineral Resources Group — Copper Business briefing (13 April 2023) — as of 2023-04-13
Byproduct and co-product commodities
- Byproduct 1
- Gold, silver, molybdenum (in concentrate)moderateEscondida TRS (S-K 1300) — as of 2022-06-30
Reported production
| Metal | Quantity | Basis | Period | Source |
|---|---|---|---|---|
| Copper (total) | 1304900 t | total | FY2025 (year to 30 Jun 2025) (100% basis) | BHP Operational Review FY2025high |
| Payable copper in concentrate | 1127200 t | concentrate | FY2025 (100% basis) | BHP Operational Review FY2025high |
| Copper cathode (SX-EW) | 177700 t | saleable product | FY2025 (100% basis) | BHP Operational Review FY2025high |
Public technical reporting
S-K 1300 (primary) — Technical Report Summary – Minera Escondida Limitada (Pre-Feasibility Study level), 2022, filed by BHP (SEC EDGAR, 20-F exhibit) on SEC EDGARhighTechnical Report Summary – Minera Escondida Limitada (Pre-Feasibility Study level)
Non-code source — BHP Operational Review for the year ended 30 June 2025, 2025, filed by BHPhighBHP Operational Review for the year ended 30 June 2025
United States (SEC) · expected language: Mineral Resource / Mineral Reserve (Technical Report Summary)
Reported mineral resource and reserve
| Category | Tonnes | Grade | Contained | Cut-off | As of | Source |
|---|---|---|---|---|---|---|
| Proven+Probable | 106 Mt (Oxide; BHP 57.5% attributable basis) | 0.55 % Cu | — | — | 2022-06-30 | Escondida TRS |
| Proven+Probable | 2500 Mt (Sulphide (flotation); BHP 57.5% attributable basis) | 0.65 % Cu | — | — | 2022-06-30 | Escondida TRS |
| Proven+Probable | 952 Mt (Sulphide leach; BHP 57.5% attributable basis) | 0.45 % Cu | — | — | 2022-06-30 | Escondida TRS |
| Total Ore Reserve | 3560 Mt (BHP 57.5% attributable basis) | 0.59 % Cu | — | — | 2022-06-30 | Escondida TRS, Table 1-4 (p.26); Section 1.10, Table 1-4 (p.26 |
| Total Ore Reserve | 6187 Mt (100% MEL basis; 100%-basis reserve for the whole operation. Total material movement 17,137 Mt. Reconciles with the 3,560 Mt attributable figure at 57.5%. Use this figure (not the attributable one) whenever a 100% Escondida number is wanted.) | 0.59 % Cu | — | — | 2022-06-30 | Escondida TRS, Table 19-1 (p.206) / production schedule Fig 19-1, Table 19-1 (p.206 |
| Measured+Indicated | 1640 Mt (BHP 57.5% attributable basis) | 0.49 % Cu | — | — | 2022-06-30 | Escondida TRS |
| Inferred | 5380 Mt (BHP 57.5% attributable basis) | 0.53 % Cu | — | — | 2022-06-30 | Escondida TRS |
Figures are quoted from the filing named beside each row and are not restated, converted or aggregated here.
Processing and metallurgy
- Process route
- flotation, heap leach, bio oxidation
- Reported recovery
- oxide heap leach 62%; mixed 42%; sulphide leach (bioleach) 42%; sulphide concentrator flotation 83%
- Processing language used in the filing
- none of that family used
- Deleterious elements named
- none stated
Recovery by route: oxide heap leach 62%; mixed 42%; sulphide leach (bioleach) 42%; sulphide concentrator flotation 83%.
Escondida TRS- Process route
- not stated
- Reported recovery
- ~952 Mt of sulphide-leach reserve recovers copper at ~42%, and mixed ore at ~42% — i.e
- Processing language used in the filing
- none of that family used
- Deleterious elements named
- none stated
Large low-recovery streams: ~952 Mt of sulphide-leach reserve recovers copper at ~42%, and mixed ore at ~42% — i.e. a majority of contained copper in those streams reports to residue/tailings by design.
Escondida TRS (derived observation from recovery figures)- Process route
- flotation, heap leach, bio oxidation, SX EW
- Reported recovery
- not stated
- Processing language used in the filing
- none of that family used
- Deleterious elements named
- none stated
Processing method: Three sulphide concentrators (SAG + ball mill, rougher + column-cell cleaner flotation); oxide heap leach and sulphide bioleach pads feeding SX-EW cathode; concentrate piped ~170 km to Coloso Port. Plant capacity >422,000 t/day.
Escondida TRS + Mining-TechnologyAssessment
The 2022 S-K 1300 Technical Report Summary reports Escondida's reserves by processing route, with concentrator flotation recovering ~83% of contained copper but the oxide, mixed and sulphide-leach routes recovering only ~42-62%. Across the sulphide-leach reserve (952 Mt) and the mixed-ore stream, the majority of contained copper reports to leach residue and tailings by design, and byproduct gold, silver and molybdenum deportment is not resolved in public reporting. Public resource reporting characterises grade and bulk recovery route; it is not designed to resolve element deportment by mineral phase in the low-recovery streams or in decades of accumulated residue. Whether recoverable value resists the conventional leach/flotation split, or reports to residue, is a testable question that a DETECT characterisation is built to answer. Element deportment by mineral phase is not resolved in the public reporting located, and the figures here are machine-extracted from the cited filings and not yet independently verified.
Screening signals
Each item below is something a cited source states. Nothing here asserts that unrecovered material is present.
Reported metallurgical recovery is oxide heap leach 62%; mixed 42%; sulphide leach (bioleach) 42%; sulphide concentrator flotation 83%.
oxide heap leach 62%; mixed 42%; sulphide leach (bioleach) 42%; sulphide concentrator flotation 83%
Escondida TRSReported metallurgical recovery is ~952 Mt of sulphide-leach reserve recovers copper at ~42%, and mixed ore at ~42% — i.e.
~952 Mt of sulphide-leach reserve recovers copper at ~42%, and mixed ore at ~42% — i.e
Escondida TRS (derived observation from recovery figures)Gold, silver, molybdenum (in concentrate) is named as a byproduct or co-product commodity, and the resource statement located carries no grade or contained-metal figure for it.
Gold, silver, molybdenum (in concentrate)
Escondida TRS (S-K 1300)First production is reported as 1990, giving roughly 36 years of processing under successive process routes.
1990
Wikipedia — Escondida (fallback source; well-established)The deposit is described as Supergene-enriched porphyry copper; monzonite-granodiorite intrusions; three zones — secondary oxide, supergene sulphide, hypogene sulphide. Porphyry systems are documented as commonly carrying molybdenum, gold, silver, rhenium and tellurium as byproduct or unrecovered constituents.
Supergene-enriched porphyry copper; monzonite-granodiorite intrusions; three zones — secondary oxide, supergene sulphide, hypogene sulphide
Escondida TRS (S-K 1300)Open technical questions
Public resource reporting characterises grade and tonnage to a code standard. It is not designed to resolve element deportment by mineral phase. These are the questions this operation’s public reporting was not built to answer.
The resource statement reports contained Copper but no deportment for the gold, silver, molybdenum (in concentrate) carried in the concentrate; in which mineral phase that value resides is not resolved by the assays disclosed.
Grounded in: Gold, silver, molybdenum (in concentrate) is named as a byproduct or co-product commodity, with no separate grade in the located resource statement. source
Reported metallurgical recovery is oxide heap leach 62%; mixed 42%; sulphide leach (bioleach) 42%; sulphide concentrator flotation 83%; where the unrecovered fraction reports across concentrate, tailings and residue is not resolved by the disclosed assays.
Grounded in: The filing reports a metallurgical recovery of oxide heap leach 62%; mixed 42%; sulphide leach (bioleach) 42%; sulphide concentrator flotation 83%. source
The deposit is described as Supergene-enriched porphyry copper; public code-compliant reporting characterises grade and tonnage to a code standard but is not designed to resolve element deportment by mineral phase in this material.
Grounded in: The deposit type is reported as Supergene-enriched porphyry copper; monzonite-granodiorite intrusions; three zones — secondary oxide, supergene sulphide, hypogene sulphide. source
How those questions get answered
These are testable questions about element deportment by mineral phase, which code-compliant public reporting is not designed to resolve. A DETECT™ characterisation of a representative physical sample is the instrument built to answer them: it measures which phases host the value and how much is locked. It does not assume a result.
What was sought and not found
- Basis RESOLVED: statement tables are 57.5% attributable; Chapter 19 (Table 19-1) is 100% MEL terms. Both now captured. Grades unaffected by ownership scaling.
- Byproduct (Au/Ag/Mo) reserve grades not separately captured in this pass.
- No public element-deportment-by-mineral-phase data — state as a gap, never imply hidden value.
- Reserve/resource figures machine-extracted, not hand-verified (verification_status = machine_extracted_unreviewed).
- TRS is effective 30 Jun 2022; a newer BHP annual-report ore-reserve statement may supersede these grades/tonnes — refresh from the latest BHP Annual Report.
- Figures are machine-extracted from the cited filings and not yet independently verified by a qualified person (verification_status = machine_extracted_unreviewed). Confirm against the cited filing before external use.