tungsten
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GC: n

CT: Imagine a lump of iron the size of a tennis ball. Weigh it in your hand. Now let it drop on to your foot. How does that feel? Now imagine an identical object three times as dense. How would that feel if you dropped it? Would you ever walk again?
That metal is tungsten.
As well as being incredibly dense it is also incredibly hard and has the highest melting point of all the elements at 3,422C.
A century or so ago the world had no use for it – it was almost impossible to shape or work the stuff. Yet now we use tungsten to write with, to traverse glaciers, to emit X-rays and to destroy buildings without the use of explosives.
To understand how this happened, we need to understand the competitive forces that have shaped everything in our world, and where better to start than a mystery at the heart of the evolution of life?
For the first four billion years, life didn’t actually do much evolving. Organisms were small, simple and fairly rare. Then around 500 million years ago something extraordinary happened – the fossil records show there was an incredible explosion of life.

S: BBC – https://bbc.in/2QBG7BF (last access: 6 December 2018)

N: 1. Rare metallic element, 1796, from Swedish tungsten “calcium tungstate,” coined 1780 by its discoverer, Swedish chemist Karl Wilhelm Scheele (1742-1786) from tung “heavy” + sten “stone”. The word was used earlier as the name for calcium tungstate (1770). Atomic symbol W is from Latin wolframium, from German Wolfram “iron tungstate”.
In the other way, 1757, “woldram” come from German Wolfram, wolform “iron tungstate” (1562), of obscure etymology. It looks like “wolf-cream” (from rahm “cream”), but the second element might be Middle High German ram (German Rahm) “dirty mark, soot;” if so, perhaps “so called in sign of contempt because it was regarded of lesser value than tin and caused a considerable loss of tin during the smelting process in the furnace”. Or perhaps the word is originally a personal name, “wolf-raven”.
2. A gray-white heavy high-melting ductile hard polyvalent metallic element that resembles chromium and molybdenum in many of its properties and is used especially in carbide materials and electrical components (such as lamp filaments) and in hardening alloys (such as steel)
3. Tungsten (W), also called Wolfram, lapis ponderosus or Heavy Stone, is a silver-grey metallic element with the highest melting point of any metal (3410° C). Tungsten has a high density, high strength at elevated temperatures and extreme hardness. Its first important use, during the mid-1800s, was in the manufacture of high-speed steel. Tungsten steels are important to industry because they retain their hardness and strength at high temperatures. Sintered tungsten-carbide tools were developed in the 1920s, and account for about 60% of current tungsten consumption. Metallic tungsten is used in the electronics industry and for lightbulb filaments.
4. There are 4 important ore minerals of tungsten: scheelite, wolframite, ferberite and huebnerite, the first 2 being far more abundant than the others. Canada was a major producer of tungsten ore and concentrate until 1986, when increased exports from the People’s Republic of China caused a price collapse that eventually forced Canadian mining operations to close. In light of recent price increases some deposits are being re-evaluated and may be brought back to production. Canada’s largest tungsten deposits are located in the YT, the NWT (where there is a community named for the metal) and NB; smaller deposits are dispersed across the country.
5. Tungsten has a silvery-white luster and is brittle at room temperature. At elevated temperatures (100°–500°C – 212°–932°F), it is transformed into the ductile state. Tungsten metal is stable in air only at moderate temperatures; all high-temperature applications are therefore limited to a protective atmosphere or vacuum.
Tungsten and tungsten alloy products are used in lighting (in the form of wires, coils, and coiled coils in incandescent lamps, and as electrodes in discharge lamps), electrical engineering (high-performance switches), electronics (integrated circuits), medical engineering (x-ray targets), sport equipment (golf club components), aviation and military components (tank ammunition), and steel technology (high-speed steels). Tungsten carbide (WC) forms the main constituent in cemented carbides (also known as hard-metals); these very hard and tough materials are used for metal cutting, machining of wood, plastics and composites, mining tools, construction and wear parts, and military components. Oxides are used as phosphors, pigments, catalysts (oil industry, combustion plants), and electrochromic devices (smart windows).

S: 1. OED – https://bit.ly/2BVrKjI;”>https://bit.ly/2BVrKjI; https://bit.ly/2zKsIh4 (last access: 6 December 2018). 2. MW – https://bit.ly/2zKt3Am (last access: 6 December 2018). 3. CAE – https://bit.ly/2rnvtjK (last access 6 December 2018). 4. CAE – https://bit.ly/2rnvtjK (last access 6 December 2018). 5. CHE – https://bit.ly/2EhVrxO (last access: 6 December 2018).

SYN: wolfram

S: OED – https://bit.ly/2BVrKjI (last access: 6 December 2018); TERMIUM PLUS – https://bit.ly/2Sy0KMv (last access: 8 December 2018).

CR: electrical energy, electricity.