Tungsten
Tungsten (W) is a hard rare metal that has a melting point of 3,433 degrees Celsius and density 19.3 times that of water and 1.7times that of lead.
The chemical element, tungten, is also known as wolfram, which accounts for its chemical symbol being 'W.' It is a hard rare metal that was first isolated as such in 1783. Its ores comprise both scheelite and wolframite. As a free element, tungsten is remarkably robust especially considering the fact that its melting point is the highest of all the elements. Its density is close to that of gold and uranium and far higher than that of lead. When it contains minor amounts of impurities it is often found to be hard and brittle, a feature that makes it difficult to work. However, when in a pure state, tungsten, although still hard, is far more ductile that makes it possible to be cut with a hard steel hacksaw.
Tungsten has many uses, some of these include:
- Filaments used in incandescent light bulbs
- Target and filaments in X-ray tubes
- In producing super alloys, as small amounts of tungsten alloyed with steel greatly increased its toughness
- Wear resistant abrasives
- Cutting surfaces on knives and drills, circular saws, turning and milling tools used in metalworking and woodworking
- In the construction, petroleum and mining industry
- Military applications such at the tips of penetrating projectiles
- The jewellery industry uses sintered tungsten for the making of rings
- High density weights, counter weights, ballast keels for yachts, tail ballast for aircraft and ballast in racing cars
- 2012 Mars Science Laboratory vehicle entry portion
- Riveting dolly
- High quality darts
- Fishing lures
- Strings on musical instruments
Although tungsten carbide is referred to by manufacturers such as jewellers as being a metal, it is actually a ceramic. Rings made from tungsten carbide are extremely resistant to abrasion and will hold a burnished finish far longer than metallic tungsten, although, tungsten carbide rings are susceptible to breaking if given a sharp blow because of their brittleness.
Tungsten, when being separated from its ore is converted to tungsten oxide. This product is heated with either carbon or hydrogen to produce powdered tungsten. Owing to the fact that tungsten has such a high melting point it is not feasible to cast the tungsten into ingots. Instead, the powdered tungsten is mixed with small amounts of powdered nickel, or other metals, and sintered. It is during the sintering process that the nickel diffuses into the tungsten and forms the alloy.
In its raw form tungsten is a very hard steel grey metal that is quite brittle. It has to be reduced to its pure form before it becomes malleable enough to be worked by either extruding, drawing or forging, otherwise, tungsten objects it have be formed through the sintering process.
As at December 2011 Australia had resources of 376 kilotonnes of tungsten held in deposits on King Island and at Mount Lindsay and Kara in Tasmania, Watershed in Queensland, Mount Mulgine, Big Hill and O'Callaghans in Western Australia and Molyhil in the Northern Territory. Western Australia holds over 60 percent of Australia's known tungsten resource, Tasmania has 22 percent and Queensland has 14 percent.
Australian Mines that produce Bauxite
Gove (NT)
Up to 600 workers employed at the Gove bauxite refinery in the Northern Territory face an uncertain future as Pacific Aluminium suspends alumina production.
Ely (QLD)
The Ely Alcan Queensland Pty Ltd agreement at the Weipa bauxite mine is due to expire in 2041 but an option will give it a further 21 years extension.
Skardon River (QLD)
Gulf Alumina acquired 100 percent of the Skardon River tenement in 2011 from its koalin mining joint partner to develop the mining of bauxite at the site
Weipa (QLD)
The Weipa bauxite mine on the western side of the Cape York Peninsula in northern Queensland is both owned and operated by Rio Tinto Alcan.
Huntly (WA)
The Huntly mine in Western Australia is the largest bauxite mine in the world currently producing about 23 million tonnes of bauxite annually.
Willowdale (WA)
The Willowdale bauxite mine that commenced production in 1984 still processes 10 million tonnes of bauxite a year at the nearby Wagerup Refinery.
Worsley (WA)
The Worsley bauxite mine and alumina refinery in South West Western Australia employs more than 1,800 people and produces 4.6 million tonnes of alumina annually.
South Aurukun (QLD)
The South Aurukun bauxite tenements on the Cape York Peninsula in Far North Queensland are held by Gulf Alumina.
Marchinbar Island (NSW)
The Marchinbar Island bauxite deposit in far north Northern Territory could be mined to satisfy a growing demand from China in the near future.
Kwinana Refinery (WA)
The Kwinana refinery in WA employs around 1,000 direct employees with 60 percent living in the nearby towns of Rockingham, Cockburn and Kwinana.
Wagerup Refinery (WA)
The Alcoa owned Wagerup alumina refinery in W.A. has received governmental approval to lift alumina production from 2.6 to 2.65 million tonnes annually.
Pinjarra Alumina Refinery (WA)
The Pinjarra alumina refinery, near Mandurah south of Perth, is an important part of Alcoa's three refinery system in Western Australia.
Portland Aluminium Smelter (VIC)
The Portland Aluminium smelter in western Victoria, a joint venture operation between Alcoa, CITIC and Marubeni, caters solely to the Asian market.
Felicitas (WA)
The Felicitas bauxite project in Western Australia contains a bauxite resource of 220 million tonnes that will give it a life of mine of 25 years
South Of Embley (QLD)
Despite Rio Tinto placing its South of Embley bauxite project in Cape York, Queensland, on hold for 18 months it still considers it a 'good project.'
Bauxite Hills (QLD)
The Bauxite Hills Project on the Cape York Peninsula in Queensland is hoping to take advantage of an expected increase in the demand for Alumina.
Bald Hill (TAS)
Australian Bauxite Limited's Bald Hill mine, in Tasmania, is to start production in December, 2014. It is the first new bauxite mine in Australia, for over 35 years.
Urquhart Point (QLD)
The Urquhart Point Heavy Mineral Sands Project in Cape York in Far North Queensland is expected to begin production in mid-2015.
Amrun (QLD)
The Amrun bauxite project in far north Queensland, that was previously known as the 'South of Embley' project has been approved for development and expected to be in production by 2019.
