Name and Location
Thunderbird mineral sands project, Australia.

Client
Sheffield Resources.

Project Description
The Thunderbird deposit has measured, indicated and inferred resources of 2.62-billion tonnes at 6.5% heavy mineral sands for 170-million tonnes of contained heavy mineral sands, including a high-grade component of 740-million tonnes at 12.1% heavy mineral sands.

The deposit is characterised by large-scale, high-grade, thick, sheetlike orebody geometry; a low stripping ratio; a conventional processing flowsheet; modest preproduction capital requirements; a favourable location and logistics; and readily saleable products.

The scoping study completed on the project envisages dry mining of the Thunderbird deposit at a rate of 2 500 t/h, using large dozers and scrapers. Ore will be screened and pumped as a slurry from relocatable skid-mounted mining unit plants for further screening, scrubbing and desliming at the wet concentrator plant (WCP). Deslimed ore will be pumped to a five-stage wet concentrator circuit.

Processing water for slurrying and the WCP will be supplied by a borefield accessing the shallow freshwater aquifer underlying the deposit. Heavy mineral concentrate from the WCP will be transported to a concentrate upgrade plant (CUP), while thickened slimes, sand tails and oversize from the WCP will be codisposed in the mine void.

At the CUP, magnetic and gravity circuits will separate magnetic (ilmenite-bearing) from nonmagnetic (HiTi 80 and zircon-bearing) concentrates. Separate ilmenite and nonmagnetic circuits within a conventional mineral separation plant will produce final products of ilmenite, zircon and HiTi 80 leucoxene for transport to port.

An accommodation camp for 145 personnel will also be constructed at the mine site. Additional infrastructure will include an upgraded access road of about 35 km to the Great Northern highway.

Average yearly production, following ramp-up to a 20.8-million-tonne-a-year mining rate is estimated to be 118 200 t zircon, 545 000 t ilmenite and 21 700 t HiTi80 over an initial mine life of 32 years, which will position Sheffield as a globally significant mineral sands producer. During the first ten years, the projected annual zircon production will average 135 100 t/y.

Value
Preproduction capital is estimated at A$294-million.

Duration
Initial production is targeted for 2017.

Latest Developments
Sheffield has started a prefeasibility study (PFS), which is expected to be completed during the first quarter of 2015. Work conducted during the course of the PFS has the scope to further improve the already robust project.

Sheffield intends to complete an infill and step-out drilling programme and a resource update by the fourth quarter of 2014. Step-out drilling will target extensions of shallow, high-grade mineralisation to the north and north-east of the deposit. The discovery of additional high-grade mineralisation in this area is likely to further improve the project economics.

The PFS will include a hydrogeological study and a water drilling programme to model the impact of processing water abstraction and obtain the relevant approvals. Port and infrastructure studies are planned, as is the investigation of potential improvements to the processing flow sheet design.

Level 2 flora and vegetation and terrestrial and subterranean fauna assessments have already been completed on the project. Further baseline studies outside the immediate project area are planned during 2014.

Geotechnical drilling and analysis are planned to assist in the detailed mine planning studies.

Sheffield plans to complete a definitive feasibility study during 2015, followed by mine construction in 2016, with first production targeted for 2017.

Key Contracts and Suppliers
None stated.

On Budget and on Time?
Not stated.

Contact Details for Project Information
Sheffield Resources, tel + 61 8 6424 8440, fax +61 8 9321 1710 or email info@sheffieldresources.com.au.