Discovery Information
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Who: Clemens Winkler |
When: 1886 |
Where: Germany |
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Name Origin
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Latin: Germania (Germany). |
"Germanium" in different languages. |
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Sources
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Obtained from refining copper, zinc and lead. It can be found in argyrodite (Ag8GeS6), coal, germanite (Cu13Fe2Ge2S16), zinc ores as well as other minerals. About 80 tons are produced each year.
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Abundance
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Universe: 0.2 ppm (by weight) |
Sun: 0.2 ppm (by weight) |
Carbonaceous meteorite: 21 ppm |
Earth's Crust: 1.8 ppm |
Seawater: |
Atlantic surface: 7 x 10-8 ppm
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Atlantic deep: 1.4 x 10-7 ppm
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Pacific surface: 3.5 x 10-7 ppm
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Pacific deep: 6 x 10-6 ppm
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Uses
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Widely used in semiconductors, infrared prisms (for night vision goggles), reflectors in projectors, wide angle lenses and
dentistry.
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Germanium transistors are still used in some effects pedals by musicians who wish to reproduce the distinctive tonal character
of the "fuzz"-tone from the early rock and roll era. Vintage effects pedals known to contain germanium transistors have shown
marked increases in collector value for this reason alone.
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History
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In 1871, germanium (Latin Germania for Germany) was one of the elements that Dmitri Mendeleev predicted to exist as a missing
analogue of the silicon group (Mendeleev called it "ekasilicon"). The existence of this element was proven by Clemens Winkler in 1886. This discovery
was an important confirmation of Mendeleev's idea of element periodicity.
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The development of the germanium transistor opened the door to countless applications of solid state electronics. From 1950
through the early 1970s, this area provided an increasing market for germanium, but then high purity silicon began replacing
germanium in transistors, diodes, and rectifiers. Silicon has superior electrical properties, but requires much higher purity
samples-a purity which could not be commercially achieved in the early days. Meanwhile, demand for germanium in fiber optics
communication networks, infrared night vision systems, and polymerization catalysts increased dramatically. These end uses
represented 85% of worldwide germanium consumption for 2000.
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Notes
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Its occurrence is 0.0007% of the earth's crust. In the elemental form it is a lustrous white, brittle metalloid. When crystalized
it has a diamond cubic structure. It is a poor conductor and is used in electronics in rectifying devices and transistors.
It is also used in dental alloys. There are several compounds which contain germanium. "Germaine" or germanium hydride is a colourless gas GeH4 prepared by the action of lithium aluminium hydride on germanium halide in an ether solution. Germaine is a hazardous substance UN2192 which is classified as a poisonous gas
(2.3). It is also a flammable gas (2.1). Other compounds include : Germanium dichloride GeCl2, Germanium dioxide GeO2, Germanium tetrachloride GeCl4 this is very irritating to eyes and membranes.
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Hazards
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Certain compounds of germanium have low toxicity to mammals, but have toxic effects against certain bacteria. This property makes these compounds useful as chemotherapeutic agents.
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