Question: When did the Australian rail freight operator, whose main commodities included Aluminium oxide, become part of QR National?

full_context: Document 1: Zirconium dioxide: Zirconium dioxide (ZrO2 ), sometimes known as zirconia (not to be confused with zircon), is a white crystalline oxide of zirconium. Its most naturally occurring form, with a monoclinic crystalline structure, is the mineral baddeleyite. A dopant stabilized cubic structured zirconia, cubic zirconia, is synthesized in various colours for use as a gemstone and a diamond simulant.
Document 2: Regional Rail Logistics: Regional Rail Logistics is a rail freight operator based in New South Wales, Australia. They operate containerised freight services three days a week between the Riverina towns of Junee and Cootamundra to Port Botany in Sydney, using rolling stock of Melbourne rail operator El Zorro.
Document 3: Australian Railroad Group: Australian Railroad Group (ARG) was an Australian rail freight operator. It began operations in Western Australia on 17 December 2000 following its purchase of the Westrail freight business. It was purchased by QR National in June 2006. The main commodities hauled by ARG included grain, mineral sands, alumina, bauxite, coal, woodchips, quartz, nickel and iron ore around Western Australia. In June 2011 it ceased trading as a separate brand, and became part of QR National.
Document 4: Alum root: Alum root or Alumroot is a common name for some species of two different genera of flowering plants:
Document 5: Zircon: Zircon ( or ) is a mineral belonging to the group of nesosilicates. Its chemical name is zirconium silicate and its corresponding chemical formula is ZrSiO. A common empirical formula showing some of the range of substitution in zircon is (Zr, REE)(SiO)(OH). Zircon forms in silicate melts with large proportions of high field strength incompatible elements. For example, hafnium is almost always present in quantities ranging from 1 to 4%. The crystal structure of zircon is tetragonal crystal system. The natural color of zircon varies between colorless, yellow-golden, red, brown, blue, and green. Colorless specimens that show gem quality are a popular substitute for diamond and are also known as "Matura diamond".
Document 6: South Australian Railways East-West Stock: This article outlines the history of the 24 Corten steel vehicles with corrugated sides, constructed by the South Australian Railways and primarily used on the East-West Express from Adelaide to Port Pirie. The South Australian Railways broad gauge system had been extended north in 1937 to meet a southern extension from Port Augusta on the Commonwealth Railways' standard gauge system, creating Port Pirie as a break-of-gauge and transshipment point. To encourage passengers to use the line despite the inconvenience of changing trains, in 1947 the Cafeteria Car was constructed and used on the services to and from Adelaide, in conjunction with the mid-1930s Steel carriage fleet. In 1964 the first airconditioned sitting cars entered regular service on the East-West Express, and construction of those continued through to 1967 with a total of nine sitting cars and fourteen vans.
Document 7: Qantas Freight: Qantas Freight is a subsidiary company of Qantas, responsible for the air cargo operations of the Qantas group. It is the owner of freight airline Express Freighters Australia, freight forwarder Qantas Courier and trucking company Jets Transport Express. Qantas Freight was also a partner in two joint ventures with Australia Post: Australian air Express, specialising in door-to-door package delivery, and Star Track Express, a road freight company. In November 2012 Qantas Freight fully acquired Australia air Express and divested its shareholding in Star Track to Australia Post. Qantas Freight was also the owner of Asian-based freight forwarder DPEX Worldwide until that company was acquired by its competitor Toll Holdings in 2010.
Document 8: Genesee &amp; Wyoming Australia: Genesee & Wyoming Australia (GWA) is an Australian rail freight operator based in Adelaide, South Australia. It is a subsidiary of Genesee & Wyoming and was formed in June 2006 to run the South Australian operations of the Australian Railroad Group.
Document 9: Chrysoberyl: The mineral or gemstone chrysoberyl is an aluminate of beryllium with the formula BeAlO. The name chrysoberyl is derived from the Greek words χρυσός "chrysos" and βήρυλλος "beryllos", meaning "a gold-white spar". Despite the similarity of their names, chrysoberyl and beryl are two completely different gemstones, although they both contain beryllium. Chrysoberyl is the third-hardest frequently encountered natural gemstone and lies at 8.5 on the hardness scale, between corundum (9) and topaz (8).
Document 10: Interail: Interail was an Australian rail freight operator owned by QR National. In June 2011 it ceased trading as a separate brand, and became part of QR National.
Document 11: Aurizon: Aurizon Holdings Limited is a publicly listed rail freight company in Australia. Formerly owned by the Government of Queensland, its assets were transferred to a new company, QR National Limited, in July 2010 in preparation for it being floated on the Australian Securities Exchange in November 2010. Aurizon is Australia's largest rail freight company.
Document 12: Public float of QR National: In 2010 the Queensland Government split the government owned rail operator Queensland Rail into two companies: the government owned passenger operator Queensland Rail and the freight operator QR National (now Aurizon), the latter to be floated in late 2010.
Document 13: Aluminium oxide: Aluminium oxide (British English) or aluminum oxide (American English) is a chemical compound of aluminium and oxygen with the chemical formula Al O . It is the most commonly occurring of several aluminium oxides, and specifically identified as aluminium(III) oxide. It is commonly called alumina, and may also be called aloxide, aloxite, or alundum depending on particular forms or applications. It occurs naturally in its crystalline polymorphic phase α-AlO as the mineral corundum, varieties of which form the precious gemstones ruby and sapphire. AlO is significant in its use to produce aluminium metal, as an abrasive owing to its hardness, and as a refractory material owing to its high melting point.
Document 14: Zirconium: Zirconium is a chemical element with symbol Zr and atomic number 40. The name "zirconium" is taken from the name of the mineral zircon, the most important source of zirconium. The word "zircon" comes from the Persian word "zargun" زرگون, meaning "gold-colored". It is a lustrous, grey-white, strong transition metal that resembles hafnium and, to a lesser extent, titanium. Zirconium is mainly used as a refractory and opacifier, although small amounts are used as an alloying agent for its strong resistance to corrosion. Zirconium forms a variety of inorganic and organometallic compounds such as zirconium dioxide and zirconocene dichloride, respectively. Five isotopes occur naturally, three of which are stable. Zirconium compounds have no known biological role.
Document 15: Aluminium alloy: Aluminium alloys (or aluminum alloys; see spelling differences) are alloys in which aluminium (Al) is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon, tin and zinc. There are two principal classifications, namely casting alloys and wrought alloys, both of which are further subdivided into the categories heat-treatable and non-heat-treatable. About 85% of aluminium is used for wrought products, for example rolled plate, foils and extrusions. Cast aluminium alloys yield cost-effective products due to the low melting point, although they generally have lower tensile strengths than wrought alloys. The most important cast aluminium alloy system is Al–Si, where the high levels of silicon (4.0–13%) contribute to give good casting characteristics. Aluminium alloys are widely used in engineering structures and components where light weight or corrosion resistance is required.
ground_truth: June 2011