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PROPERTIESAfter a period in which the price of Gallium increased up to a peak of 688 US$/kg in 2011, the price has declined. In 2013 the price of Gallium decreased continuously. 1 Gallium is a critical material because of the increase of the global demand and the concentration of the limited existing reserves in politically sensitive areas. ORIGINThe leading producer is China, which has increased its production capacity by a factor of five 2. Its competitors are Kazakhstan and Ukraine. As it is primarily obtained from the circulation liquor in the Bayer process for aluminium oxide manufacture, gallium is a by-product of aluminium production and is not extracted in its own right. SOLUTIONSAn alternative to GaAs is SiGe because they have similar properties required for high-power and high-frequency electronics. While an alternative to GaN in LEDs and laser diodes is Zinc oxide (ZnO), an II-VI compound semiconductor. However, currently substitution of Gallium in optoelectronic devices (LEDs, laser diodes, photodetectors and solar cells) is limitedly possible and only at loss of performance. The LED industry waste dust contains primarily gallium as GaN. To develop treatment and recycling technology of these GaN bearing e-waste, leaching is the primary stage. Without pre-treatment, the gallium leaching was only 4.91 w/w % using 4M HCl, 100°C and pulp density of 20g/L. After mechano-chemical processing, both these processes achieved 73.68 w/w % of gallium leaching at their optimum condition. REFERENCES: Periodic Table of Videos, accessed December 2014. https://en.wikipedia.org/wiki/Gallium - wikipedia 1 Greber, J.F. (2000) Gallium and Gallium Compounds, in: Ullmann's Encyclopediea of Industrial Chemistry, pp. 335-340. Weinheim: Wiley-VCH Verlag GmbH & Co. KgaA 2 strategic metal Investments Ltd. (2013) By-Product Metals. The aluminium-gallium relationship Pt. II – strategic Metal report Uses and properties: John Emsley, Nature’s Building Blocks: An A-Z Guide to the Elements, Oxford University Press, New York, 2nd Edition, 2011. Thomas Jefferson National Accelerator Facility - Office of Science Education, It’s Elemental - The Periodic Table of Elements, accessed December 2014. Back to the index Alvarez Laura, Di Bartolomeo Giulia, Mantovani Giulia, Perdisa Martina ANTIMONY Antimony is a semimetal: in the periodic table we can find it as Sb (V group, period 5, atomic number: 51). It's a shining metal, white or grey if left in contact with air for a long time. Antimony at his native state is very often covered by a white-yellowish crust of ossidation. Etimology The antimony' symbol in the periodic table brings back to his ancient etymology: from Latin,stibium little stick which indicated the make up used for the eyebrows. Instead the name antimony seems to have different origins: many think that it comes from Greek anti= against and monos= the one who lives alone, because monks assumed it to contrast the effects of fasting poisoning themselves unawares. An etymology more accredited refers to the fact thats in nature antimony can't be found pure but always in company of others elements in many minerals. Uses e Properties 
Antimony was known (Pliny the Elder called it stibium) and used in the past (IV millennium b.C) as a medicine and eye-makeup. His therapeutic properties are used still today in emetic medicines as in the past, “eternal pills” that, after pocked, you could be reused. In our days, antimony is used in differents fields: it's used the most for lead alloyds, because it increases the hardness and mechanical strength for batteries; another peculiar use is as flame retardant in clothes and toys for children, seat covers in planes and cars, in nail-varnish, paints, glass, pottery . It is used also in alloys for the production of typefaces, tracer bullets, cable sheathing, matches, pipes, infrades, semiconductures, catalysts for esterification. Origin, Provenance e Quotation 
Despite the fact antimony is not a plentiful element, it can be found in more than 100 minerals; the most usual is the sulfide Sb2S3, .It is estimated that the presence of antimony in the Earth’s crust is between 0.2 and 0.5 ppm. The biggest producer at the moment is China. Antimony is not quoted on stock exchange but it’s presumed that its cost will rase up to $20,000 per ton in 2020 Solutions As a flame retardant antimony can be replaced by organic compounds; however, even if its substitutes are easier to find, this element has a more effective yield. In production of lead alloys and glasses, antimony can easily replace them without losing big performances and without an increase of prices; on the other size, Atimony is the best material in products like rubbers and catalysts. 
Back to the index Alvarez Laura, Di Bartolomeo Giulia, Mantovani Giulia, Perdisa Martina Beryllium Beryllium (Be) is an alkaline earth metal; in the periodic table it is placed in period 2 of the II group, atomic number 4. It is a steel grey metal, rigid, light but fragile. 
Etimology: Beryllium’s name comes from the Greek beryllos, a light blue precious stone of Indian origins. Beryllium was discovered (as an oxide) by L.N. Vauquelin who gave to it the name of glucinium (from greek glykys, sweet, beacuse of the sweet taste of its salts) instead its current name was given by F. Wohler who isolated it in 1828. Uses and Properties 
Beryllium is used in nuclear industry: in fact it is a neutron multiplier, i.e. it absorbs a neutron and it releases two. Fermi used this property in the first nuclear reactors. Beryllium is used as a binder in the production copper-beryllium, in military and aerospace industries, for the construction of gyroscopes, in parts of computer, for clock or watch springs, in tubes of fluorescent lighting ( this use was abandoned because it caused the berylliosis to the workers who produced them) and in anti-spark tools.
Beryllium is a very expensive metal, so it is used only where its properties are essential and a substitute which brings to the desired result has not been found yet, because performance and lenght are reduced excessively. Health Effects Beryllium is dangerous if breathed: effects depend on the time and on the amount of exposition. Some people have developed an irritation to beryllium: for intance, they can show an inflammation of the respiratory tract even after a long time since the exposition to beryllium; this desease is called “berylliosis”. It makes you feel weak and tired; it can also provoke anorexia, weight loss and it can bring, in some cases, to heart diseases.  Back to the index Samira Al Sadi, Caterina Albarello, Matteo Bianchi Nb Niobium 
Niobium is a transition metal which belongs to the fifth group and the fifth period of the periodic table. It was named by the German scientist Heinrich Rose, who discovered it in 1844. In Greek mythology Niobe was Tantalus’ daughter. The suffix -ium was added to mean it was a metal. Most of this metal is found in Brazil, but recently some new deposits have recently been found in Canada. It's found in nature as the oxide called pirochlorine.
It is a raw critical element because most of it comes from just one country, and an economic or political crisis could seriously compromise the availability of this material. 
Origins The biggest pirochlorine lode in the world can be found in Araxà (south-east of Brazil). It's owned by Companhia Brasileira de Metalurgia e Mineracão (CBMM), that provides 70% of worldwide provisions. Others big lodes are in Amazonas (25.5% of provisions) and Goiàs (1.4% of provisions). Niobium is pulled out from underground tunnels in Canada and from strip mines in Brazil. After its extraction it's transferred to a plant in which it is transformed in niobium. In Uganda Ruanda and Congo a war was fought for the possession of a pirochlorine lode. Substitutions Some solutions are Vanadium, Titanium, Tungsten and Tantalium, whereas they are less efficient and malleable, more expensive and heavier than Niobium.  
Titanium Vanadium BIBLIOGRAPHY: http://www.ing.unitn.it/~colombo/COLUMBIO/columbio.htm#_DISPONIBILITÁ CRM_InnoNet Back to the index Samira Al Sadi, Caterina Albarello, Matteo Bianchi Mg Magnesium 
Magnesium is the lightest structural metal. It belong to the second group and the third period of the periodic table. It was named magnesium because it was found in a Greek region called Magnesia. The suffix -ium was added to mean it was a metal. Uses and properties It has a good formability, a medium strength, an excellent corrosion resistance, high quality anodising ability as well as weldiability and an excellent malleability. Because of these properties it is used, alloyed with aluminium to produce food packaging and beverage cans, scaffolding in the naval industry and the harbors.  
Economical-political characteristics Five years ago, magnesium's cost was twice that of aluminium (about $4.00 per kg). China now produces one-half the world's supply and has forced magnesium prices down to nearly those of aluminum ($1.60 per kg). 
Origins China is the dominant supplier of magnesium, with approximately 80% of the world market share. The United States has traditionally been the major world supplier of this metal, supplying 45% of world production even as recently as 1995. Substitutions Magnesium can be substituted with iron in Aluminium alloys which are very hard and which lead to a deterioration of the corrosion properties of Aluminium. Some alloys are made by adding manganese, which makes them ductile, resulting in good formability.   Aluminium
BIBLIOGRAPHY http://pubs.acs.org/cen/80th/print/magnesium.html https://en.wikipedia.org/wiki/Magnesium#Production Back to the index Di Sipio Luigi, Laffusa Pasquale, Momi Sabrina, Stamati Dragos Platinoids (Ru, Rh, Pd, Os, Ir, Pt) The platinum Group metals (also called platinum metals) are ruthenium, rhodium, palladium, osmium, iridum and platinum. PROPERTY The platinum group metals are characterized by a set of common properties: chemical inertia, gloss, High melting point, resistance to corrosion and oxidation at high temperature, low coefficient of thermal expansion, and mechanical stability and thermal durability, capacity catalytic. All these properties are exploited in various industrial applications. The density, melting point, and the boiling point increases from the upper right toward the lower left (in the periodic table) ; the highest and most stable oxidation numbers decrease from bottom left to top right (inside of the periodic table)
Identity Card ETHYMOLOGY
USES Platinum is used in jewellery and watchmaking (it has high costs due to the raw material's high cost and the difficult processing). It is used in the chemical industry for the inalterability of the air and the resistance to most chemical agents. For the resistance to high temperatures it is used in the aeronautical field. To remove the exhaust gases it is used in catalytic converters in cars. In medicine it is used in pacemakers for exmple, while it is much used in dentistry. Iridium is mainly used in alloys with platinum to manufacture precision instruments, surgical instruments, fountain pens, weights and standard lengths, it is also used in high temperature applications. RECOVERY AND RECYCLING What is obtained in precious metals from dixies? A platinum, rhodium and palladium treasure. The recycling of these precious materials will help to conserve natural reserves which are all the more valuable because they are very limited: think about the global estimate for rhodium that is less than 4,000 tons. A big North European company could recover from the catalysts, in 1996, 5 tons of platinum, 13 of palladium and 0.5 of rhodium. QUOTATION
SOURCES The Platinum can be often found with other similar metals and mainly in river’s alluvial settles in Colombia, in Ontario, on the Ural and in the western USA. Platinum is a by-product of the treatment of the Nichel’s minerals. Although the report of the Platinum is in the average 2 parts over 1 million, the large quantities of the treated mineral make affordable the extraction
CURIOSITIES Platinum is used in the new technologies to treat migraine, in particolar with the invention of the “Sopraorbital Trigeminal Stimulator”. A small circle of Platinum rechargeable like a smartphone that operates like a neuronstimulator, leaving impulses in quantities innocuous for the skin and for the bones but useful to treat the headache. The unito of measure metre is distance between two points A and B established on a bar, kept at the temperature of 0° Celsius made of Platiniridium, adepte to not be conditioned from the same bar’s inflexions .. The example is kept since 1889 at the “Bureau International des poids et mesures” of Sèvres in France.
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