The lead was finally introduced to the London Stock Exchange, LME, in 1920.
Lead is used largely for batteries or accumulators of energy.
Specific characteristics of the lead futures contract
Contract: Lead to 99,970% with reference to BS EN 12659: 1999
Lot Size: 25 tons (with a tolerance of +/-2)
Margin per Lot: $4,600
The lead is the chemical element with atomic number 82. Its symbol is Pb.
It is a soft metal, heavy, malleable. Bluish white freshly cut, weathered turns dark gray. Lead is used in the building industry, in the production of batteries for vehicles and projectiles for firearms. Lead is a component of pewter and of metal alloys used for welding.It is the lead that its compounds are toxic.
Lead is a blue-white metal very tender, dense, ductile and malleable; It also has a relatively low electrical conductivity. Can be made harder by the addition of a small amount of antimony.
It is very resistant to corrosion; is not affected by sulfuric acid, but dissolves in nitric acid.
It was discovered very old-age in Anatolia have been found lead beads dating back to around 6500 BC. He speaks in Egyptian Papyrus of 1550 BC and in the book of exodus-possibly because its minerals are found everywhere and are easy to blend, and because lead itself is a material easy to work with.
Lead pipes and structures dating back to the Roman Empire are still in existence and in service today. Lead smelting is part of the industrial history of many countries.
Its name comes from the Latin plumbum that presumably comes from the Greek??????, (pelios, blackish blue), or from Sanskrit bahu-mala (very dirty). From the Latin name derives its symbol, Pb.
Until the 1980s the tetraethyl lead was a component of gasoline, used as an additive to increase octane. Due to its toxicity and its ability to "poison" the catalysts used to reduce pollution created by car exhaust, was abandoned in favor of other additives. Other additives in use that have replaced the lead, such as benzene and [tolene]], are classified as carcinogenic.
The mines of the earliest models of used lead pencils instead of graphite.
Lead native state exists, but is quite rare. It is usually found associated with zinc, silver and copper, mainly is then retrieved with these metals. The most important lead mineral is galena (lead sulphide) which contains 86.6%. Much of the lead in use today comes from recycled sources.
In the mines of lead ores are extracted for drilling or outburst, then ground. The ore is then separated from the inert rock for flotation and then melted, producing a concentrated the 97% lead that, for gradual cooling, is freed from debris that emerge on its surface. The remaining molten lead is then refined to further mergers in the air flow, and a purity of 99.9%.
Its compounds are toxic by inhalation and if swallowed.
Lead is a poisonous metal that can damage the nervous system (especially in children) and cause disease of the brain and blood. The exposure to lead or its salts, especially soluble ones, or PbO oxide2, can cause kidney and abdominal pain-type pains. Some historians ascribe to the lead (for pipes for drinking water and the use of lead acetate, called sugar of lead, to sweeten the wine) the cause of dementia that has plagued many of the Roman emperors.
Concerns about lead's role in mental retardation in children has led to a general reduction of its use (lead exposure has been linked to schizophrenia; paints containing lead have been withdrawn from the market in all industrialized countries. However, many old homes still contain lead in their paint, and in the case of renovation you should never remove the old layers of varnish sanding because it would produce particulate matter containing lead, which would be breathe.