The Cloudbreak, Christmas Creek and Kutayi deposits lie within the Chichester Ranges, in northern Western Australia. Iron mineralisation is hosted by the Nammuldi Member which is the lowest member of the late Archaean aged Marra Mamba Iron Formation (MMIF). The Nammuldi Member is characterised by extensive, thick and podded iron rich bands, separated by equally extensive units of siliceous and carbonate rich chert and shale. The Nammuldi Member in the Chichester Range is interpreted to be up to 60 metres in true thickness. Underlying the Nammuldi Member rocks are black shales and volcanic rocks belonging to the Jeerinah Formation. Extended periods of tectonic activity have variably folded and faulted these rocks, together with weak metamorphism. Subsequent erosion and hardcapping or lateritic processes have altered these rocks, and present outcrop of Nammuldi Member represents a ridge of lowlying hills (relief up to 30 metres) throughout the prospect areas. These ridges are recognised as the Chichester Ranges.

Iron mineralisation characteristically comprises hematite, goethite and ocherous goethite, with variable degrees of alteration between these minerals. The main gangue minerals are kaolinite, quartz and gibbsite, with minor amounts of carbonates, either calcite or dolomite.

Iron is enriched in the parent BIF (iron layers banded with cherts and lesser carbonates) by processes of supergene and/or hypogene enrichment. In both processes, the original iron, which is present as magnetite bands within the BIF, is oxidised to hematite and goethite. Contemporaneous with the iron enrichment, the original gangue minerals are partially to fully leached out or may be replaced by iron minerals. These processes increase the iron content of the BIF depending upon the degree of enrichment. A volume loss of up to 35 per cent can occur with enrichment due to loss of gangue minerals. Microplaty hematite (MplH) is recognised in varying degrees throughout Fortescue’s Chichester Range deposits. This is interpreted to occur due to hypogene enrichment of the MMIF in proximity to tectonic structures (faults or tight folds), which have allowed upward fluid flow, and low-grade metamorphism of the parent rock, resulting in extensive hematite mineralisation.

The majority of the iron mineralisation is hosted by the Nammuldi Member which is the lowest member of the late Archaean aged Marra Mamba Iron Formation (MMIF). The NammuldiMember is characterised by extensive, thick and podded iron rich bands, separated by equally extensive units of siliceous and carbonate rich chert and shale. The Nammuldi Member in the Chichester Range is interpreted to be up to 60m in truethickness. Underlying the Nammuldi Member rocks are black shales and volcanic rocksbelonging to the Jeerinah Formation. Limited iron mineralisation also occurs in the overlying CID and Tertiary alluvial material.

Cloudbreak and Christmas Creek - Up to ~80km along strike and up to 5km plan width. Upper limit of mineralised domain is located between 0m to 125m below the surface. Lower limit of mineralised domain is located between 1m and 130m below the surface. The average thickness of the mineralised domain is 7.0m and the range of thickness is 1m to 28m.

Solomon Hub Deposits – Firetail, Kings and Queens. The Solomon Project area is situated approximately 60km to the north of the Tom Price township in the northern Hamersley ranges. Outcropping geology in the project area is dominated by the Dales Gorge, Whaleback Shale and Joffre Members of the Brockman Iron Formation which hosts large bedded iron deposits (BID) throughout the Hamersley Province. The Firetail deposit comprises the majority of BID tonnes at Solomon, where geologically favourable environments have allowed for the formation and preservation of large tonnages of bedded iron mineralisation.

Incised into the bedrock geology are regional palaeochannel systems, predominantly one to two kilometres in width, and stretching for tens of kilometres. During the Miocene period, deep chemical weathering and erosion of iron rich material into these fluvial channels has formed channel iron deposits (CID). The CID is subdivided into an upper ‘hard CID’ and a lower ‘ochreous CID’, there is also a semi-continuous middle CID layer which is difficult to detect with RC drilling. Clay lenses within the CID are observed as semi-discrete bands, often several meters thick. The clay lenses are somewhat discontinuous and of a poddy nature although often traceable between drill holes. CID of approximately 40km strike length is preserved in the Kings CID system, with an additional 25km of CID located in the Serenity deposit to the west. Other CID occurrences are also known throughout the Solomon project area. The material overlying the CID (and other areas) has been eroded from adjacent mineralised and un-mineralised bedrock. This clastic material is concentrated into horizons of elevated iron grade termed detrital iron deposits (DID), which forms part of the sequence of overlying late Tertiary aged alluvial and colluvial deposits.

Mineralisation within the Solomon area is hosted by buried Channel Iron Deposits (CID), Bedded mineralisation (BID and Detrital mineralisation (DID). Outcropping geology in the area is the Dales Gorge, Whaleback Shale and Joffre Members of the Brockman Iron Formation which contain the BID mineralisation. Incised into this bedrock geology are the large Channel systems which contain the DID and CID mineralisation.

Kings: The CID mineralisation has a strike length of 20km and a width of 1 - 2km. Though the CID mineralisation outcrops in the southeast corner of the deposit, the majority of the CID mineralisation is buried and occurs at depths of up to 40m below surface and the defined mineralised units have a thickness of between 1m and 65m.

Queens: The CID mineralisation has a strike length of 10km and a width of 0.5 - 1km. The CID mineralisation is buried and occurs at depths of up to 60m below surface and the defined mineralised units are between 1m and 65m thick.

Firetail: The bedded mineralisation has a strike length of 7km and outcrops on the north and south limbs of an anticline. Mineralisation is strata bound, has an average thickness of 20m and extends to a depth of 100m below surface in places.

The Eliwana deposit occurs on the southern limb of the Jeerinah anticline in the western Hamersley Province. The deposit covers a narrow zone that follows the outcrop of mineralised Brockman and Marra Mamba Iron Formations, with Tertiary sediments in the valleys separating these formations. Iron mineralisation predominantly occurs as bedded iron deposits (BID) with some detrital iron deposits (DID). The mineralisation, which occurs at surface and extends to depths of 350m below surface, is variably distributed across an area of approximately 40km along strike and 3.5km across strike.

The Marra Mamba Iron Formation outcrops in the north and dips towards the south around 15 to 20 degrees. Tertiary sediments occur in the valley. Minor occurrences of the Oakover Formation are mapped outcropping in the western portion of the project area. The main area of mineralisation occurs over an area 11km along strike and 400m across strike. Mount Newman Mineralisation occurs at surface in the north and at depths up to 200m to the south. The thickness of mineralisation averages 20m throughout the deposit and is found up to 50m in areas.

At Eliwana mineralisation is distributed variably within an area of approximately 40km in an east west direction and 3.5km in a north south direction. Mineralisation occurs at surface and extends to depths of up to 350 metres below the ground surface. The reported tonnes and grade in the Mineral Resource occur at depths of up to 350 metres.

Chichester Hub Operation
Cloudbreak
The mining model is based on strip mining. Mining at Cloudbreak will continue to be carried out as open pit strip mining.

The pits are developed progressively, where a starter pit is opened (with overburden from the starter pit placed in a small overburden stockpile). As the mining face progresses, the open pit is progressively backfilled and rehabilitated.

The majority of the ore will be mined using surface miners. Surface miners can cutto an accuracy of 0.1 m and can extract ore without the need for drilling, blasting, or primary crushers to crush ore. Ore is loaded from the surface miner into trucks for transfer to the OPF.

Christmas Creek
Drill and blast
Drilling and blasting is used to allow areas of hard rock overburden to be removed. Drilling and blasting is undertaken in accordance with current operational procedures, which generally incorporate the following steps:
1. A series of holes are drilled into the rock.
2. The holes are filled with explosives and detonated.
3. The rock breaks up or collapses after detonation and the rock rubble is then removed.
4. The cleared rock face is ready for drilling and the steps are repeated.

Strip Mining
Mining will continue to be undertaken using the same mining methodology currently in place, consisting of conventional truck and shovel mining and strip mining. Typically, strip mining involves pits being developed in thin strips, around 150-200 m wide by 800 m long. Each mining area is mined to suit a particular set of constraints and requirements.

When mining commences in a new pit, the overburden is removed from the first two adjacent strip and placed just beyond the ore body limits close to the last strip to be mined in the sequence. Ore is then mined from the first strip.

When the ore in the second strip is removed, removal of overburden from fourth strip commences and material is backfilled into the void of second strip, while concurrently mining the ore in the third strip. This process progresses through the mining area.

When the ore from the penultimate strip is removed, waste from the first strip (stockpiled nearby) is backfilled into that void. When the ore from the last strip is removed, the remainder of the stockpiled waste from the first two strip is backfilled into the final void. Completed pits are backfilled at minimum to the pre-mining groundwater level. Waste rock and overburden material are generally removed using a combination of shovels, excavators and trucks. The majority of overburden is used to backfill completed pits.

Solomon Hub Operation
Mining will continue to employ conventional open pit methods of drill and blast followed by load and haul, similar to the methods employed at other open cut mines in the Pilbara. Material will be drilled and blasted on nominally 5 m or 12 m benches2 for ore and waste, and then mined by hydraulic backhoe configured excavators, taking into account blast induced swell, into haul trucks.

Existing waste dumps will be used until pit voids are available for backfilling.

It has been assumed that current mining methods will continue to be used in the future, the block size in the models is appropriate for this.

Western Hub Operation (Eliwana)
It is assumed that mining will be carried out with medium to large scale mining equipment, bench heights may vary depending on mining studies. These methods will be similar to analogous Fortescue deposits where conventional: truck & shovel/excavator; drill & blast and; grade control methods are used. The impact of dilution will be assessed as part of the mining studies.

Mine scheduling
Chichester mineralisation is combined with Solomon BID (principally from Firetail) and with Eliwana, to manufacture the BID blended products – West Pilbara Fines, Fortescue Blend and Super Special Fines. The Kings Fines CID product is predominantly sourced from the Kings and Queens deposits and will include a proportion of BID and detritaliron deposit (DID) mineralisation incidental to mining the CID channels. Scheduling aims to maintain the target blended ore quality and maximise net present value (NPV). In general terms this equates to deferring higher strip ratio, higher mining cost mineralisation until later in the collective scheduled mine life.

Blending between sites takes advantage of impurity synergies that maximise the ore supply relative to products being sourced from single sites. The proportion of each of the collective BID and CID products will change with time depending on the respective ore quality being delivered from individual deposits. The constituent products are manufactured at the port by blending individual trains onto port stockpiles.

The scheduling inventory is initially collected into ore “bins” based on Fe and impurity cut-offs. Since mineralisation distributions and presentation varies with time, so too may the shorter term effective ore cutoff grade.

Chichester Hub Operation
Cloudbreak
Crushing/sizing Facilities
The crushing and sizing facilities consist of a series of crushers designed to handle standard sized ore and large ROM oversize rocks generated in drill and blast operations, pit floor windrow cleanup and pit wall batter scraping at the mine. The crushing and sizing process will size material to less than 250 – 300 mm such that it can be transported by conveyor to the OPF.

Christmas Creek
Remote Crushing
An RCH currently operates approximately 6.5 km east of the main processing facilities at Christmas Creek. The RCH sizes the mined material to prepare it for processing in the OPF (ore processing facilities). The RCH consists of:
- ROM bin
- mineral sizer
- gyratory crusher
- crushed ore vault.
Once material has been crushed, it is transported to OPF2 by an overland conveyor.

On April 2021, SIMPEC removed the old crushers and replacing them with two new C160 jaw crushers.

Solomon Hub Operation
Crushing will involve combinations of primary, secondary and tertiary crushing.

Western Hub (Eliwana)
Components of the OPF (screens, crushers (jaw/cone/mills), conveyors:
- ROM Bin (BN101)
- Apron feeder (AF101)
- Primary crusher (Gyratory crusher, CRG101)
- Feed = -1,500mm
- Product = -250mm
- Hybrid feeders (Low profile feeders, BF221 & BF211)
- Scalping screens (SN211 & SN221)
- Secondary crushers (Sizer crushers, SZ211 & SZ221)
- Feed = -250mm
- Product = -150mm
- Belt feeders (BF311, BF321, & BF331)
- Tertiary Crushers (Cone crushers, CRC311, CRC 321, & CRC331)
- Feed = -150mm
- Product = -31.5mm
- Product screens (SN311, SN321, & SN331)
- Vibrating pan feeders (VF311, VF321, VF322, & VF331)
- Plant Conveyors (CV211, CV221, CV212, CV222, CV311, CV321, CV331, CV701 & CV702)

Chichester Hub Operation
Chichester Hub in the Chichester Ranges, comprising the Cloudbreak and Christmas Creek mines, has an annual production capacity of approximately 100mtpa from three Ore Processing Facilities (OPFs). Consistent and sustained performance delivered from the OPFs has allowed us to optimise our product strategy through enhanced blending and beneficiation, supporting iron grades and reducing impurities.

This has contributed to lower mining cut-off grades, as weoptimise ore bodies with sustainably lower strip ratios. To further enhance our ore, the Christmas Creek OPF infrastructure has been upgraded to include a Wet High Intensity Magnetic Separator (WHIMS) to recover high grade iron from the finer ore fed through the plants, helping to improve product yield and reduce total mining volumes.

Cloudbreak utilises relocatable conveyors which can be moved, lengthened or shortened once an area is mined. The conveyors now cover 10km, extended from ........