Tallebung (100% SKY)

The Tallebung Project is located approximately 70km north-west of Condobolin in central-western NSW.

Tallebung stands as an open-pit, technology enabled, near-term tin development. Uniquely placed to provide secure tin supply, to feed irreplaceable and rapidly expanding tin demand, essential in semiconductor, electronics and solar PV technologies.

The Tallebung Tin Project is the site of large-scale historical tin mining in central Western NSW with tin first discovered in the 1890s. SKY is progressively defining a large-scale hardrock tin resource with recent higher-grade tin zones discovered on the margins of the known deposit and exceptional metallurgical performance demonstrated across the entire known deposit.

The shallow, open-pit tin veins combined with the ideal nature of the tin, hosted as large, discrete grains of simple tin-oxide (cassiterite minerals), all ideally lends itself to low-cost tin production advantages, including exceptional X-ray based ore sorting performance, demonstrated to upgrade the tin up to 44x, prior to low-cost gravity separation to produce a saleable tin concentrate

Latest Mineral Resource Estimate and Exploration Target – JORC-012

An Exploration Target at Tallebung of approximately 23 – 32 Mt at a grade ranging between 0.14 – 0.17% tin at a cut-off grade of 0.08% tin has been defined from the drilling completed to date along with an inferred and indicated JORC-2012 MRE of 15.6Mt 0.15% tin at a 0.08% tin cut-off grade. TOMRA Ore Sorting has shown that the grade can be quintupled (5x) to over 0.7% tin with over 98% recovery of tin.

Table 1: Tallebung MRE showing total tonnage, grade and contained metals at a 0.08% Tin cut-off grade. NB: WO₃ refers to the Tungsten reported as an oxide as it is likely to be a significant by-product. Additionally, mtu refers to metric tonne units which Tungsten is conventionally reported as, 1 mtu = 10 kg WO₃ (SKY ASX Announcement 23 January 2024).

For further details on the maiden Exploration Target and MRE, please see the ASX Announcement here

Project Sustainability

SKY aims to be an industry leader in environmental and sustainability practices. Tin at Tallebung is in a mineral called cassiterite and forms large “nuggets” which makes it exceptionally easy and economical to process as well as presenting many environmental benefits.

The extraordinarily coarse liberation size of the cassiterite due to the “nuggety” nature means that it does not require large amounts of energy to crush and grind. Additionally, the application of TOMRA Ore Sorting technology and gravity concentration methods both work remarkably well to save large amounts of power and water in the production of the tin.

Demonstration of Ore Sorting Process – Video courtesy of Carlos Crowley Vazquez, BOEq & TOMRA Ore Sorting Solutions

The TOMRA Ore Sorting process at Tallebung requires no use of water or chemicals and reduces the total mass for further processing by 80%. Therefore, the technology significantly reduces the amount of water used for processing by 80% or 4/5th and further work is planned to determine the suitability of the rejected Ore Sorting mass for use as barren waste material. This material may then be useful for sheeting roads or to be sold for use in other regional construction projects.

In addition to the Ore Sorting benefits, the gravity processing method only uses water through the plant to concentrate the tin at Tallebung and recycles this water throughout the plant. This further reduces any future water requirements and avoids using large quantities of chemicals required by some other tin concentration operations. The simple gravity concentrate method and the TOMRA Ore Sorting reduce any waste and does not require the treatment and storage of large amounts of chemicals from mining and processing at Tallebung.

Figure 1: Tallebung Tin Project – Plan showing extent of the current Exploration Target along with the drillholes sampled for the TOMRA variability study testwork shown in yellow. TOMRA ore sorting shows a consistent 3-6x upgrade across the entire deposit, significantly increasing average grade from 0.15% Tin to over 0.70% Tin.

Mining History of the Tallebung Tin Field

The project is centred on the historic Tallebung Tin Field where numerous phases of mining activity have occurred over more than 100 years since its discovery in the 1890s. This activity targeted the high-grade quartz-lodes and the alluvial/colluvial material with a combined estimated historic production of 3,350 tonnes of tin concentrate. SKY is now targeting the bulk tonnage tin mineralisation underlying these areas of historic mining.

Due to the past mining activity at Tallebung, much of the costly infrastructure required for a mining operation is already in place. This includes powerlines to site, all-weather haul roads to site and within the site and an established past water supply enabling lower infrastructure set up costs for future mining operations.

Next Steps

Work will continue with the aim to further improve the promising prospects of potential low-cost tin production at Tallebung. This will include further drilling to explore for extensions to the shallow, higher-grade discoveries made in TBRC078 and TBRC090 (11@ 1.02% tin from 64m & 10m @ 0.69% tin from 23m respectively). In addition to these planned aggressive resource expansion drilling campaigns, work will also continue on metallurgical and mining economic studies in parallel over the coming months.

To rapidly advance the metallurgical and mining studies, a trenching program commenced last year has been sampled to obtain trench assays and continue to increase the geological understanding at Tallebung. The results will allow the Company to increase both the size and confidence in the MRE. Once assays for the channel samples are returned, 3-4 zones will be selected for bulk sampling.

To mimic mining, the bulk samples will be taken from below these trenches, in deeper cuts underneath and also perpendicular to the strike of the mineralisation to give representative bulk samples of the Tallebung tin mineralisation for metallurgical testwork.

Following sampling, the bulk samples will be crushed and sorted via XRT ore sorting in the full-scale ore sorter plant at the TOMRA Ore Sorting Test Facility in Sydney. The sorted samples will then be sent to ALS Burnie in Tasmania for grinding and processing in a pilot-scale gravity plant to produce a tin concentrate.

This program will provide a sample tin concentrate to use for marketing purposes and customer engagement. Given the favourable nature of the tin mineralisation at Tallebung, it is anticipated that the tin concentrate will be very desirable for downstream markets.

On the back of these works, mining economic studies will be prepared for late Q2 CY2025.

Concurrently with the technical studies above, environmental studies for development approvals are already being progressed. This demonstrates SKY’s strong conviction to the Tallebung Project and is in preparation to realise the potential of the project and bring it into production as quickly as possible.

Environmental Studies and Development Approvals

Environmental studies required to secure key development approvals continue to be expedited, with an initial background biodiversity study completed and a weather station installed as well as the groundwater monitoring bores already installed.

The installation of a weather station will provide vital data for the environmental studies needed for the development approvals process. This installation complements the work already completed on these studies, with the groundwater monitoring bores already installed and geochemical studies well advanced.

The installation of these data collectors and the biodiversity and geochemical studies are all in preparation to quickly advance the development approvals process required to commence mining of the Tallebung Tin Project.