The Birthplace of the Aus Iron Ore industry EarthCache

An Earthcahe placed near the place where the Australian Iron Ore industry started. I quick short detour off the Eyre Highway will have you there to have a look

This cache is similar to the one I placed on the Lincoln Highway about 50km south at the Duke Iron Ore Operations

This cache has been place outside the Former BHP Billiton (Future Onesteel Iron Knob operations. The Iron ore to be mined here (around 2013) supplies the blast furnace in Whyalla for the production of steel, and crushed product to load directly onto ships for export. Formerly owned by BHP Billiton and sold off when Iron Ore was discovered in Western Australia in the Pilbara. Onesteel took over the operations and a few other mine further north to carry on with the supply of ore to the blast furnace.

Hematite Fe2O3 and contains 69.9% Fe (Iron Magnetite Fe3O4 and contains 74.2% Fe (Iron). The major rock types mined for the production of metallic iron are massive hematite, limonite [FeO(OH).nH2O], which provide a 'high-grade' ore, and banded metasedimentary (sedimentary rock that shows evidence of having been subjected to metamorphism) ironstone, magnetite-rich metasomatite, to a much lesser degree, rocks rich in siderite, rocks rich in chamosite which provide a 'low-grade' ore

Currently most of the iron ore mined in the world comes from large deposits of massive hematite most commonly a banded iron formation (BIF). Two of the best known Australian examples of massive hematite deposits are Tom Price and Mount Whaleback in the Hamersley Range, Western Australia. Another type of high-grade deposit is limonite ore formed in ancient river channels, e.g. Yandicoogina, Hamersley Basin, Western Australia The consensus model for formation of massive hematite ore is enrichment by the passage of fluids, which remove the non-iron-bearing minerals (dominantly chert), to a much lesser extent add iron minerals.

High-grade ore generally has a cut off grade of ~>60% Fe. Historically it has provided a direct feed to smelters either as a raw lump or fines, also in a processed form such as sinter or pellets. There are emerging markets for new varieties of feedstock. Examples include sintered iron carbide and 'DRI' ore, which is natural ore with Fe >69% and low levels of specific trace elements suitable as feed to 'direct reduction' smelters.

Low-grade Ore is a term applied to iron-rich rocks with cut-off grades in the range of 25 - 30% Fe. It was the main supply of iron ore for many centuries of the World's early history of production of iron.

Since the 1950s North America's main supply has been low-grade ore. The dominant economic iron mineral in low-grade ore is magnetite. The ore may be easily beneficiated by a process know as wet-magnetic separation - this process has been employed for many decades in North America. Major deposits of this rock type occur in the Middleback Range within a BIF host. The ore was formed by supergene enrichment process include the predominance of meteoric water circulation with oxidation and chemical weathering. The descending meteoric waters oxidize the primary sulfide ore minerals and redistribute the metallic ore elements.) of host BIF with both structural and mineralogical controls on ore distribution Age of ore formation is put at 1800–1650 Ma.

In 1915 the first major iron ore mine in Australia was opened at a massive hematite deposit at Iron Knob by BHP Pty Ltd. Since then some 200 Mt of high-grade ore has been mined from five massive hematite deposits in the Middleback Range. From 1915 to 1965 the Iron Monarch and Iron Baron–Iron Prince mines were the main supply of ore for Australia's iron and steel industry. The favourable logistics of low cost of ore extraction and the nearby portsite at Whyalla, led BHP to establish an integrated steelworks at Whyalla in 1964.

Iron Baron was closed in 1995 and Iron Monarch was closed in 1998. Current operating mines in the Middleback Ranges are Iron Knight, Iron Duchess, Iron Duke and Iron Magnet. In 2000 BHP Steel Pty Ltd divested itself of all long products businesses which included the Whyalla operations and its attached iron ore resources.

From this announcement OneSteel emerged as a totally independent competitive, steel maker and producer of long steel products. They are the current major producers of iron ore from massive hematite deposits in the South Middleback Range. Iron ore and its uses
Elemental Iron (Fe) is ranked fourth in abundance in the earth's crust and is the major constituent of the Earth's core. It rarely occurs in nature as the native metal.

The pure metal is silvery white, very ductile, strongly magnetic and melts at 1528° C Iron accounts for approximately 95% of all metals used by modern industrial society. Metallic iron is most commonly produced from the smelting of iron ore to produce pig iron. Steel is a processed form of pig iron with impurities such as silicon, phosphorus and sulphur removed and with a reduction in the carbon content. Globally, steel's versatility is unsurpassed. Wrought iron (low carbon) and cast iron (pig iron) also have important markets. One of the most ubiquitous products in Australia is corrugated iron, a structural sheet steel shaped into parallel furrows and ridges.

It was invented by Henry Robinson Palmer in 1828 in London and quickly became popular for roofing and farm buildings. Iron metal may be produced from the smelting of certain iron compounds. Their concentration in economic proportions is referred to as 'iron ore'. Other well known uses of iron compounds are:

• iron sulphate used as fungicide, the oxalate of iron in

photographic development, limonite, goethite, hematite as pigments

and abrasives, magnetite in the production of industrial electrodes and also for washing coal

• iron chloride and nitrate used as mordents and industrial

reagents in the production of several types of inks

• iron carbonyl as a catalyser of many chemical reactions

• micaceous hematite as a protective paint on steel superstructures.

Source: http://www.minerals.pir.sa.gov.au/geology/mineral_resources/commodities/iron_ore

To claim the cache please have look around GZ and discribe the rocks seen.
Look Specifically at:
Colour
Weight
General shape (round, square)
Textures
Hardness

Thanks

Enjoy!!!!!