| Aluminium is the most abundant metal on earth's crust | | | | of reflecting heat and light. |
| and is silvery white in colour. Aluminium is well-known | | | | Aluminium, in the form of a fine powder, is used in a |
| and well-used for its low density and ability to resist | | | | range of products from paints, rocket fuels, explosives, |
| corrosion. The corrosion resistance is due to a thin | | | | and chemical reductant. Most of the modern mirrors |
| layer of aluminium oxide that forms when the metal is | | | | are made using a thin reflective coating of aluminium |
| exposed to air. It is non-magnetic and non-sparking, and | | | | on the back surface of the sheet of float glass. |
| does not dissolve in alcohol. Aluminium is a good | | | | Telescope mirrors are also made of aluminium coating |
| thermal and electrical conductor. | | | | for good reflecting ability. |
| Aluminium is extracted from the principal ore, bauxite, | | | | Friedrich Wohler was the first to isolate the metal in |
| which is mined using open cut techniques. The bauxite | | | | 1827. But the metal has been long used since the |
| is purified using the Bayer process. | | | | ancient Roman times. Though it had not been isolated |
| The wide use of aluminium is due to the versatility of | | | | till the 19th century, the compounds of aluminium had |
| the metal. Its lightness, good thermal and electrical | | | | been used by Romans as dyeing mordants and |
| conductivity, malleability, tensile strength, high reflectivity | | | | astringents for dressing wounds. |
| etc, makes it suitable for use in building apartments to | | | | Aluminium does not have any known function in the |
| aircrafts, electric wires to food storage containers, and | | | | living cells and also known to produce toxic effects in |
| many others. Many commercial and military aircraft are | | | | higher concentrations. It can get deposited in bone and |
| made predominantly of aluminium. The metal makes | | | | central nervous system and competes with calcium |
| the linings of grilles, wheels, air-conditioners, automatic | | | | for absorption. In very high doses, it can cause |
| transmissions, engine blocks and radiators. The aircraft | | | | neurotoxicity and is known to alter the functioning of |
| engines, skins, landing gear, frames and interiors too, | | | | the blood-brain barrier. Those who are allergic to |
| are made of aluminium. | | | | aluminium may experience dermatitis, digestive |
| Being highly malleable, aluminium is easily fabricated into | | | | disorders, bone pain, muscle weakness, anemia, |
| sheets of various levels of thickness ranging from | | | | impaired iron absorption, seizures, growth retardation in |
| aluminium foils, sheets, shapes, rods, tubes and wires. It | | | | children, spinal deformities, etc. Antiperspirants |
| does not loose strength in extreme temperatures, and | | | | containing aluminium may increase the risk of breast |
| is easily recyclable. It also has properties of being highly | | | | cancer and aluminium has been implicated as a factor |
| reflective and is used in reflectors in stoves, infrared | | | | in Alzheimer's disease although no conclusive evidence |
| dryers, lighting equipment and wave guides. It is used | | | | has been cited. |
| as an insulating material in buildings due to its property | | | | |