Rare earths

In the everyday life of the industry today, you can often find such rare metals like titanium, tantalum, cesium, molybdenum, hafnium and zirconium. But there were times when no one heard anything about them, and knew almost nothing. The same fate was experienced by rare earths - a group of chemical elements, among which the main ones are cerium, lanthanum, neodymium, praseodymium and a heavy element of thorium.

The same fate was experienced by rare earths - a group of chemical elements, among which the main ones are cerium, lanthanum, neodymium, praseodymium and a heavy element of thorium

Quickly found its use of hafnium. The slightest admixture of it to the alloys, of which threads make electric light bulbs, increase the endurance of the thread several times. Zirconium has found application in enamels of earthenware, lithium - in dry elements, tantalum - in the filaments of light bulbs, titanium - in resistant white paints, beryllium - in light alloys.

For some time scientists did not know where to apply the rare earths. Until the end of the 19th century the talented Viennese chemist Auer did not make an interesting discovery: if in a simple gas flame a piece of thorium is added to the rare earths, then they, when heated, significantly increase the brightness of the gas burner. He decided to use this discovery to illuminate cities that were then covered with gas. True, rare earths of thorium were not found in nature often, and their practical use seemed an unrealizable undertaking. But, Auer did not give up and soon in Brazil, on the shore of Atlantic Ocean, rare earths of thorium and mineral monazite were discovered.

After that, in the factories of Vienna from the delicate fabric began to weave caps, which impregnated with solutions of salts of thorium and other rare earths. Then the tissue was gently burned and a gentle cap was obtained, which was called Auer's, which was already used in lighting. But it turned out that most of the thorium is consumed and only a few other elements from the group of rare earths, and a significant amount of salts, especially cerium, forms waste products.

Only after twenty-five years have they learned that the alloy of rare earths with iron upon impact against steel, it is easy to produce hot sparks at a temperature of 150-2000 C, which easily ignite gasoline, cotton wool or a towel. So there were lighters with "creams". But this invention, after all, did not give real application to all the scum of rare earths.

Later it turned out that some metals of the group rare earths can stain in bright and beautiful colors glass and crystal, giving them a golden, yellow, red or purple. From such glass began to make utensils, glasses, vases. Red glass was particularly valuable, and it was used on roads for traffic lights, as the light of such traffic lights penetrates through the fog.

Laboratories around the world are working diligently to use the minerals containing rare land, and as a result of many thousands of experiments, new ideas are born that lead to successful applications.

Tools