Caspin Resources (ASX: CPN) lifts Kelpie tin resource 45% as Bygoo development case advances

Caspin Resources Limited (ASX: CPN), the Australian mineral exploration company developing the Bygoo Tin Project in New South Wales, has reported a 45% increase in contained tin at its Kelpie deposit following updated geological modelling and drilling. The revised Mineral Resource Estimate comprises 6.5 million tonnes grading 0.43% tin, containing approximately 28,000 tonnes of the metal. Announced on 12 October 2026, the estimate includes a first Indicated resource component and places the full reported resource within an optimised open-pit shell. The increase strengthens the project’s resource base, but an economically viable mining operation has not yet been demonstrated through an Ore Reserve or completed development study.

How did Caspin Resources increase the Kelpie tin resource by 45% during its 2026 exploration programme?

Caspin Resources increased the Kelpie deposit’s contained tin estimate from approximately 19,300 tonnes in the September 2025 maiden resource to 28,000 tonnes in the October 2026 update. The increase followed infill and extension drilling, a revised geological interpretation and the incorporation of additional mineralised areas. Cube Consulting prepared the updated estimate under the JORC Code 2012 framework using approximately 30,000 metres of historical and recent drilling. The estimate reflects both new exploration information and an improved understanding of the deposit’s geological structure.

The reported tonnage increased substantially from approximately 3.94 million tonnes in the maiden estimate to 6.5 million tonnes. At the same time, the average reported tin grade moved from roughly 0.50% to 0.43%, showing that the larger contained-metal figure was driven principally by a much greater quantity of mineralised material rather than an improvement in overall grade. Those changes are compatible with the reported increase in contained metal, although different resource models and assumptions also influence direct year-to-year comparisons. The size of the resource is now more substantial, but grade distribution and mining selectivity will remain important to project economics.

The Kelpie estimate includes mineralisation across areas such as the Dumbrell’s and Stewart’s zones, with new work also highlighting the significance of the Errol’s Zone. Caspin Resources previously reported a 20-metre intersection grading 2.11% tin from 107 metres in the Errol’s discovery area. An individual high-grade drill intersection does not represent the average grade of the entire deposit, but it provides information relevant to continuity and future exploration targeting. Additional drilling could help establish whether those higher-grade zones can be incorporated into a more robust mine plan.

Why does the new Indicated Mineral Resource matter for the Bygoo Tin Project’s mine development plans?

The updated estimate contains approximately 1.4 million tonnes grading 0.47% tin in the Indicated category, representing around 7,000 tonnes of contained metal. Another 5.1 million tonnes grading approximately 0.41% tin remains in the Inferred category, accounting for about 21,000 tonnes of contained metal. Indicated material therefore represents approximately 25% of the reported contained tin but only about 22% of the resource tonnage, based on rounded published figures. This distinction is relevant because the higher-confidence classification covers only a minority of the total deposit.

An Indicated Mineral Resource is supported by sufficient geological information to estimate mineralisation with greater confidence than an Inferred resource. It can provide a stronger basis for subsequent technical and economic assessments, while Inferred material carries greater uncertainty regarding continuity, grade and tonnage. The presence of an Indicated component represents measurable progress from the earlier resource stage. Nevertheless, Caspin Resources has not declared an Ore Reserve, which would require additional mining, metallurgical, economic and other modifying-factor assessments.

The large Inferred component creates both opportunity and development uncertainty. Further infill drilling may support classification upgrades if geological continuity and grade are confirmed, but there is no guarantee that all the currently estimated material will achieve a higher-confidence status. Resource conversion also matters for the reliability of future mine schedules, which require dependable estimates of ore grade and tonnage over time. Additional exploration therefore has a direct role in strengthening the technical foundation for a potential development rather than merely increasing the headline resource figure.

What does the optimised open-pit shell reveal about Caspin Resources’ Kelpie development potential?

The October estimate has been constrained within an optimised open-pit shell, providing a framework for considering which mineralised material may have reasonable prospects for eventual economic extraction under selected assumptions. The model incorporates parameters including mining geometry, processing costs, metallurgical recovery and an assumed tin price. It is an important step in resource reporting because it considers a potential mining configuration rather than counting every identified mineralised block regardless of its location. However, an optimised pit shell is not equivalent to a completed feasibility study or evidence that construction would be profitable.

The resource optimisation used an assumed tin price of approximately A$64,285 per tonne and overall metallurgical recovery of 80%, alongside specified processing and operating cost assumptions. These are modelling inputs rather than realised selling prices, binding operating costs or confirmed commercial recoveries. Changes in tin prices, dilution, mining costs, recovery rates or pit design could alter the quantity of material considered economically attractive in a future study. The resulting development case will therefore be sensitive to assumptions that still require more detailed engineering and validation.

The updated model includes mineralisation extending to approximately 200 metres within the pit-constrained resource across key zones. Geological evidence also indicates mineralisation beyond parts of the modelled resource boundary, including at depth. That creates possibilities for future resource growth, although deeper material may not have the same extraction economics as shallower ore. Caspin Resources will need to assess the relationship between additional resource tonnes, mine design and cost before treating extensions as equivalent to existing open-pit material.

Can preliminary tin recovery results support an economically viable processing operation at Kelpie?

Caspin Resources has conducted preliminary metallurgical testing to investigate how tin-bearing minerals at Kelpie may be recovered into a saleable concentrate. Gravity-only processing produced recovery of approximately 59%, with a concentrate grading about 58.3% tin. Incorporating flotation increased the reported overall recovery to approximately 84%, while concentrate grade was approximately 53.6% tin. These results provide useful early information about processing options, but they do not yet establish recovery performance for a full-scale commercial plant.

The difference between 59% and 84% recovery is commercially important because it changes how much contained tin could potentially be captured from processed ore. Higher recovery can improve payable metal output from the same feed, but additional processing stages may also involve greater capital expenditure, operating costs and technical complexity. Concentrate quality, impurities, mass recovery and customer specifications will also affect potential product economics. A processing route should therefore be judged by the combined effect of recovery, cost and saleability rather than recovery percentage alone.

Caspin Resources’ optimisation assumptions include a recovery rate of 80%, which is broadly consistent with the encouraging preliminary results from combined processing. Nevertheless, further test work will be necessary to establish whether comparable recovery can be achieved across representative ore types and over different stages of a possible mine’s life. Variation in mineralogy and ore hardness can influence processing performance and energy requirements. Metallurgical confirmation will be especially important before the company can produce reliable operating cost and project return estimates.

How much additional exploration potential remains at the Kelpie and Bygoo tin deposits in New South Wales?

The revised geological model has identified a roughly 200-metre gap in effective drilling between the Dumbrell’s and Errol’s areas, particularly below approximately 100 metres from surface. That gap provides a defined exploration target rather than evidence that continuous economically recoverable mineralisation has already been established. Caspin Resources has also reported encouraging geological observations from recent drilling along down-plunge extensions. Future assays and additional drill intersections will determine whether these geological interpretations can support another resource expansion.

Four recently completed diamond holes at the Dumbrell’s and Stewart’s zones were excluded from the October resource estimate because assay results had not yet been received. The holes encountered strong alteration associated with the mineralised system, including one approximately 80-metre step-out down plunge from an existing drilling position. Such observations can guide further exploration, but alteration alone does not establish the grade or economic significance of the intervals. The pending assay data will therefore be important for evaluating the continuity and quality of mineralisation beyond the current model.

Caspin Resources expects reverse-circulation drilling to resume in November 2026, alongside continued infill and extension work. The company is also advancing planning for additional exploration targets across the wider Bygoo Tin Project, including Ardlethan East, Ardlethan South and Taylor’s Hill. These areas could contribute future opportunities if exploration identifies mineralisation of sufficient scale and grade. Their potential should remain separate from the currently reported Kelpie resource until supported by new drilling and resource estimates.

What financial and technical milestones must Caspin Resources achieve before Kelpie can become a producing tin mine?

The resource upgrade provides a stronger platform for development assessment, but several technical stages remain before a mine construction decision can be supported. Further metallurgical work, environmental baseline investigations, resource classification improvements and a detailed economic assessment will be needed. These activities will help define potential mining methods, processing capacity, capital costs, operating costs and project returns. None of those future estimates should be inferred directly from the resource’s contained-metal value.

A meaningful financial assessment must distinguish the theoretical gross value of contained tin from the cash proceeds a mining project might eventually earn. The reported 28,000 tonnes of contained tin represent metal estimated to occur within the Mineral Resource, not an equivalent quantity of refined tin available for immediate sale. Mining dilution, processing recovery, payable concentrate terms, operating expenditure, development capital and timing would all influence the ultimate economics. Applying the prevailing tin price directly to contained metal would therefore overstate what the resource announcement establishes.

For shareholders, the October update adds scale and an initial higher-confidence component to the Kelpie resource, while the next milestones will determine how much of that resource can support a commercial development plan. Positive assays from the pending diamond holes could extend the geological model, and infill drilling could improve resource confidence. Metallurgical and environmental work will increasingly determine whether those geological improvements translate into a credible mining project. A future economic study incorporating validated costs, recoveries and mine scheduling would provide a more decisive measure of the Bygoo Tin Project’s development potential.

Key takeaways from Caspin Resources’ 45% Kelpie tin resource increase at the Bygoo Tin Project

• Caspin Resources reported a 45% increase in contained tin at Kelpie.
• The updated estimate is 6.5 million tonnes grading 0.43% tin.
• Total contained tin has increased to approximately 28,000 tonnes.
• Indicated material comprises around 7,000 tonnes of contained tin.
• Most of the resource remains in the lower-confidence Inferred category.
• The resource is constrained within an optimised open-pit shell.
• No Ore Reserve or completed development feasibility study has been reported.
• Preliminary recovery improved from approximately 59% using gravity alone to 84% with flotation.
• Four diamond-hole assay results remain outstanding.
• Further drilling is planned for November 2026, alongside development-related technical studies.