Cobra's Wudinna Keeps 91% of Recovery on 40% Less Reagent

Original announcement by cruxinvestor on

Company
Cobra Resources
Ticker
COBR
Exchange
Unavailable
Region
South Australia
Primary commodity
Rare earth
Secondary commodities
Uranium
Document categories
Metallurgy, Economic study
Extracted
2026-09-17 19:38:02 UTC

Analysis by Minestarters Atlas

Minestarters Atlas analysis

Summary

Cobra Resources has completed desorption testing at its Wudinna rare earth project, establishing a measured recovery curve for both the Boland and Head prospects. The tests demonstrate that significant NdPr and HREE recoveries can be maintained even with a 40% reduction in ammonium sulfate concentration or by using acidified groundwater alone.

Reasoning: The desorption test results provide a quantified technical envelope for the project's economics, replacing single-point assumptions with a measured response curve, which significantly de-risks the metallurgical component of the upcoming scoping study.

Positive factors

  • Measured recovery curve established across multiple reagent strengths and pH levels
  • High recovery retention (91%+) when reducing reagent concentration by 40%
  • Significant 'reagent-free' floor established via acidified groundwater
  • In situ recovery (ISR) method identified as cost-effective and amenable to mineralization

Negative factors

  • Head prospect shows significantly lower absolute NdPr recovery compared to Boland
  • Commercial reagent consumption and preferred operating conditions not yet determined

Facts used in scoring: 5

Classification and evidence

Mill Routeneutral

Processing via mill or concentrator (CIL, CIP, tank leach, flotation).

Why it applies: The project utilizes in situ recovery (ISR) which is a solution-based extraction method.

Evidence · text

“That confinement lets the deposit be worked by in situ recovery (ISR), a method that dissolves the metal underground instead of excavating it.”

Bench Scale Onlynegative

Only preliminary bench tests completed — no locked-cycle or pilot work.

Why it applies: The results are derived from 24-hour desorption tests on bulk composites, which are bench-scale/screening level.

Evidence · text

“Bench-scale testing indicates the mineralization is amenable to ISR recovery techniques.”

Multi-Domain Testedpositive

Variability across ore domains (oxide, transition, fresh) has been addressed.

Why it applies: 2 distinct composites were tested

Extracted facts

Stored fact records: 5. Some facts used in scoring do not have a stored record.

Metallurgical Results (5)

desorption testsWudinna · neodymium and praseodymiumRecovery: 77 %Head Grade: 605Head Grade Unit: ppmView all details
Link to this fact

Identity

Project
Wudinna
Commodity
neodymium and praseodymium
Region
australia_sa
Reported Region
South Australia
Ticker
COBR

Test Work

Program Status
preliminary
Test Type
desorption tests
Processing Route
in situ recovery (ISR)
Sample
Boland composite, 0.5 M AMSUL, pH 3

Recovery

Recovery
77 %
Head Grade
605
Head Grade Unit
ppm

Review

Needs Review
No
Historical
No

Dates

Event date
2026-09-17T00:00:00.000Z

Reasoning: High recovery at full strength reagent concentration.

Evidence · text

“At pH 3, the Boland composite recovered 77% of its neodymium and praseodymium (NdPr)”
desorption testsWudinna · neodymium and praseodymiumRecovery: 70 %Head Grade: 605Head Grade Unit: ppmView all details
Link to this fact

Identity

Project
Wudinna
Commodity
neodymium and praseodymium
Region
australia_sa
Reported Region
South Australia
Ticker
COBR

Test Work

Program Status
preliminary
Test Type
desorption tests
Processing Route
in situ recovery (ISR)
Sample
Boland composite, 0.3 M AMSUL, pH 3

Recovery

Recovery
70 %
Head Grade
605
Head Grade Unit
ppm

Review

Needs Review
No
Historical
No

Dates

Event date
2026-09-17T00:00:00.000Z

Reasoning: Demonstrates high efficiency in reagent reduction.

Positive factors

  • Maintains 91% of the 0.5M recovery with 40% less reagent

Evidence · text

“Moving to 0.3 M, a 40% reduction in reagent concentration, returned 70% NdPr”
desorption testsWudinna · neodymium and praseodymiumRecovery: 51 %Head Grade: 605Head Grade Unit: ppmView all details
Link to this fact

Identity

Project
Wudinna
Commodity
neodymium and praseodymium
Region
australia_sa
Reported Region
South Australia
Ticker
COBR

Test Work

Program Status
preliminary
Test Type
desorption tests
Processing Route
in situ recovery (ISR)
Sample
Boland composite, acidified groundwater (no AMSUL), pH 3

Recovery

Recovery
51 %
Head Grade
605
Head Grade Unit
ppm

Review

Needs Review
No
Historical
No

Dates

Event date
2026-09-17T00:00:00.000Z

Reasoning: Provides a baseline for minimum reagent-free recovery.

Positive factors

  • Establishes a significant recovery floor without external reagent

Evidence · text

“acidified site groundwater with no added AMSUL still recovered 51% NdPr”
desorption testsWudinna · neodymium and praseodymiumRecovery: 40 %Head Grade: 706Head Grade Unit: ppmView all details
Link to this fact

Identity

Project
Wudinna
Commodity
neodymium and praseodymium
Region
australia_sa
Reported Region
South Australia
Ticker
COBR

Test Work

Program Status
preliminary
Test Type
desorption tests
Processing Route
in situ recovery (ISR)
Sample
Head composite, 0.5 M AMSUL, pH 3

Recovery

Recovery
40 %
Head Grade
706
Head Grade Unit
ppm

Review

Needs Review
No
Historical
No

Dates

Event date
2026-09-17T00:00:00.000Z

Reasoning: Lower absolute recovery levels at the Head prospect.

Negative factors

  • Significantly lower absolute recovery compared to Boland

Evidence · text

“At 0.5 M and pH 3, the Head prospect recovered 40% NdPr”
desorption testsWudinna · uraniumRecovery: 5 %View all details
Link to this fact

Identity

Project
Wudinna
Commodity
uranium
Region
australia_sa
Reported Region
South Australia
Ticker
COBR

Test Work

Program Status
preliminary
Test Type
desorption tests
Processing Route
in situ recovery (ISR)
Sample
Boland composite, 0.5 M vs 0.0 M AMSUL, pH 3

Recovery

Recovery
5 %

Review

Needs Review
No
Historical
No

Dates

Event date
2026-09-17T00:00:00.000Z

Reasoning: Shows uranium recovery is highly sensitive to reagent presence.

Negative factors

  • Uranium recovery drops significantly when reagent is removed

Evidence · text

“reducing AMSUL from 0.5 M to 0.0 M reduced uranium recovery from 29% to 5%”

How Atlas produces this analysis

Minestarters Atlas uses automated extraction to summarize mining announcements, identify reported measurements, and classify supporting evidence. Sentiment reflects the extracted narrative and classification rules; it is an interpretation, not a reported measurement. Evidence quotes and context are provided where available. Missing data, low-confidence results, and review flags indicate limitations. Check the original publisher announcement before relying on an interpretation.