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T he term heavy mineral sands is generally used to refer to placer type deposits of zircon, ilmenite, rutile and leucoxene but also by nature other minerals which may occur in the same or similar deposits such as staurolite, garnet and chromite. The deposits are usually formed by concentration due to the specific gravity of the mineral grains. Zircon, used in high value markets such as ceramic glazes, refractories and abrasives, is the most valuable component and so highzircon sands are a major focus for exploration and development. Next in importance are the titanium minerals such as ilmenite, rutile and leucoxene, much of which ends up being processed into the white pigment, titanium dioxide. China and other developing economies are driving demand for zircon, with urbanisation increasing floor space construction and therefore demand for ceramic tiles with zircon glazes. Key producers Production of mineral sands is centred on Australia, Africa and the US. In Australia, Iluka Resources stated recently that it has options to increase zircon production at its JacinthAmbrosia operation in South Australia, and is planning a de-bottlenecking program in 2011 while evaluating options to achieve a more substantial acceleration of mining, with a view to implementation in 2012. A re-optimisation of the Jacinth-Ambrosia ore body, associated with higher zircon prices and reflecting operating experience to date, may increase the Jacinth-Ambrosia reserve base, underpinning higher production and/or a longer mine life. Comprising two contiguous deposits, Jacinth and Ambrosia are located in the Eucla Basin of South Australia, approximately 800 km from Adelaide. Jacinth-Ambrosia is capable of supplying approximately 25% of global zircon supply, producing approximately 300,000 t of zircon in its initial years of production. The deposits are expected to produce approximately 2.8 Mt of zircon and 350,000 t of high grade titanium dioxide, mainly rutile and approximately 1.5 Mt of ilmenite, over their expected economic life, which is at least 10 years through to 2021. Heavy mineral concentrate is transported a distance of 270 km to port for subsequent transport, by ship to Iluka’s mineral processing facilities at Narngulu, near Geraldton in Western Australia. Iluka uses conventional dry mining methods with overburden removal by scraper and actual ore mining by dozer into a dozer trap. In addition to operating its own fleets, Iluka uses contractors in some cases. Abigroup Mining Services maintains scraper fleets at Iluka’s Kulwin mineral sands project in the Murray Basin where the company is completing an extended three year mining contract. The project is expected to be completed in December 2011. Four new Caterpillar 657 scrapers are employed to remove overburden waste material. The fleet is also employed to assist in the construction of tailing storage facilities. Based in Picton in the south west of Western Australia, Piacentini & Son is the other main Australian dry mineral sands mining contractor, with a fleet of over 90 scrapers, mainly Caterpillar 627, 631, 633, 637, 639, 651 and 657 models. In Africa, a key player is the Sierra Rutile Ltd (SRL) mine in the south west of Sierra Leone near the Imperri Hills, some 30 km from the Atlantic Ocean, on low lying coastal plains about 135 km southeast of the capital Freetown. The mine is now owned and operated by Titanium Resources Group (TRG). The mining concession is one of the largest natural rutile deposits known in the world. The mine employs a bucket ladder dredge for wet mining and conventional mineral processing methods to produce rutile, ilmenite and small amounts of zircon tailings. The mine generates its own power and operates its own port. Estimates for full year 2010 production are 70,000 t of rutile, 15,000 t of ilmenite and 5,500 t of zircon concentrate. Dredge D1 was built by Malaysia’s OCI Enginering, and is an electronically operated bucket ladder dredge with a production capacity of 1,100 t/h. It has on-board processing equipment and the off-take is pumped via a floating pipeline to the floating concentrator. The processing on the dredge consists of scrubbing followed by primary and secondary screening. The dredge product is then pumped to the wet plant where slimes are removed by primary and secondary cyclones. The de-slimed sand is then fed to a series of spiral circuits and the resultant heavy minerals are pumped to a land based stockpiling/drying area. A second dredge, D2 capsized in 2008. Future development plans include upgrading some of the existing equipment on the dredge, wet plant and land plants.