Gadolinite

Group III with electronic configuration 5s 4d . The principal ore is gadolinite (a silicate also containing lanthanides). Y2O3 containing Eu is used as a red phosphor in colour television. Yttrium iron garnets are used as microwave filters. 

The element was discovered by Nilson in 1878 in the minerals euxenite and gadolinite, which had not yet been found anywhere except in Scandinavia. By processing 10 kg of euxenite and other residues of rare-earth minerals, Nilson was able to prepare about 2g of highly pure scandium oxide. Later scientists pointed out that Nilson s scandium was idenhcal with Mendeleev s ekaboron. 

L. Rhenus, Rhine) Discovery of rhenium is generally attributed to Noddack, Tacke, and Berg, who announced in 1925 they had detected the element in platinum ore and columbite. They also found the element in gadolinite and molybdenite. By working up 660 kg of molybdenite in 1928 they were able to extract 1 g of rhenium. 

From gadolinite, a mineral named for Gadolin, a Finnish chemist. The rare earth metal is obtained from the mineral gadolinite. Gadolinia, the oxide of gadolinium, was separated by Marignac in 1880 and Lecoq de Boisbaudran independently isolated it from Mosander s yttria in 1886. 

Ytterby, a village in Sweden) Discovered by Mosander in 1843. Terbium is a member of the lanthanide or "rare earth" group of elements. It is found in cerite, gadolinite, and other minerals along with other rare earths. It is recovered commercially from monazite in which it is present to the extent of 0.03%, from xenotime, and from euxenite, a complex oxide containing 1% or more of terbia. 

L. Holmia, for Stockholm). The special absorption bands of holmium were noticed in 1878 by the Swiss chemists Delafontaine and Soret, who announced the existence of an "Element X." Cleve, of Sweden, later independently discovered the element while working on erbia earth. The element is named after cleve s native city. Holmia, the yellow oxide, was prepared by Homberg in 1911. Holmium occurs in gadolinite, monazite, and in other rare-earth minerals. It is commercially obtained from monazite, occurring in that mineral to the extent of about 0.05%. It has been isolated by the reduction of its anhydrous chloride or fluoride with calcium metal. 

Scandium is very widely but thinly distributed and its only rich mineral is the rare thortveitite, Sc2Si20v (p. 348), found in Norway, but since scandium has only small-scale commercial use, and can be obtained as a byproduct in the extraction of other materials, this is not a critical problem. Yttrium and lanthanum are invariably associated with lanthanide elements, the former (Y) with the heavier or Yttrium group lanthanides in minerals such as xenotime, M "P04 and gadolinite, M M SijOio (M = Fe, Be), and the latter (La) with the lighter or cerium group lanthanides in minerals such as monazite, M P04 and bastnaesite, M C03F. This association of similar metals is a reflection of their ionic radii. While La is similar in size to the early lanthanides which immediately follow it in the periodic table, Y , because of the steady fall in ionic radius along the lanthanide series (p. 1234), is more akin to the later lanthanides. 

The most important minerals of the lanthanide elements are monazite (phosphates of La, Ce, Pr, Nd and Sm, as well as thorium oxide) plus cerite and gadolinite (silicates of these elements). Separation is difficult because of the chemical similarity of the lanthanides. Fractional crystallization, complex formation, and selective adsorption and elution using an ion exchange resin (chromatography) are the most successful methods. 

Most orthosilicates reacted completely with poly(acrylic acid) solution an exception was andradite, CagFOg [SiOJg. Even so, the cements of gehlenite and hardystonite were very weak and affected by water. Only gadolinite and willemite formed cements of some strength which were unaffected by water, probably because one contained beryllium and iron and the other zinc. 

Rare Earth Allanite Monazite Gadolinite Fergusonite Euxenite REE, Y, U Kobe, Japan Barringer Hill, Texas Ytterby, Sweden Shatford Lake, Manitoba... 

Lars Frederik Nilson (1840-1899) found the element predicted by Dmitry Ivanovich Mendeleev (1834-1907) as "eka-boron" in the mineral gadolinite. 

It has been found that yttrocerite and gadolinite readily float with hydrohamic acid at a pH of 9-10. The proposed treatment flowsheet for beneficiation of REO-containing yttrium is presented in Figure 24.4. 

Rhenium (Re, [Xe]4/145river Rhine. Discovered (1925) by the German chemists W. Noddack, I. Noddack-Tacke and O.C. Berg in minute amounts in a sample of gadolinite (a basic silicate of Be, Fe and lanthanides). Silvery-white metal. 

Occurrence. The Re concentration is extremely low. It is found as minor component in the gadolinite and molybdenite ores. 

Erbium - the atomic number is 68 and the chemical symbol is Er. The name derives from the Swedish town of Ytterby (about 3 miles from Stockholm), where the ore gadolinite (in which it was found) was first mined. It was discovered by the Swedish surgeon and chemist Carl-Gustav Mosander in 1843 in an yttrium sample. He separated the yttriiom into yttrium, a rose colored salt... 

ORIGIN OF NAME Named for the mineral gadolinite, which was named for the French chemist Johann Gadolin. 

A stone quarry near the town of Ytterby in Sweden produces a large number of rare-earth elements. Carl Gustaf Mosander (1797-1858) discovered several rare-earths, including the rare-earth mineral gadolinite in this quarry in 1843. He was able to separate gadolinite into three separate, but closely related, rare-earth minerals that he named yttria (which was colorless), erbia (yellow color), and terbia (rose-colored). From these minerals, Mosander identified two new rare-earth elements, terbium and erbium. The terbia that was found was really a compound of terbium terbium oxide (Tb O )... 

Holmium is the 12th most abundant of the rare-earths found in the Earths crust. Although it is the 50th most abundant element on Earth, it is one of the least abundant lanthanide metals. It is found in gadolinite and the monazite sands of South Africa and Austraha and in the beach sands of Florida and the Carolinas in the United States. Monazite sand contains about a 50% mixture of the rare-earths, but only 0.05% by weight is holmium. Today, small quantities of holmium are produced by the ion-exchange process. 

Carl Gustaf Mosander, a Swedish chemist, successfully separated two rare-earths from a sample of lanthanum found in the mineral gadolinite. He then tried the same procedure with the rare-earth yttria. He was successful in separating this rare-earth into three separate rare-earths with similar names yttia, erbia, and terbia. For the next 50 years scientists confused these three elements because of their similar names and very similar chemical and physical properties. Erbia and terbia were switched around, and for some time the two rare-earths were mixed up. The confusion was settled ostensibly in 1877 when the chemistry profession had the final say in the matter. However, they also got it wrong. What we know today as erbium was originally terbium, and terbium was erbium. 

It is found in ores along with other rare-earths that were first found in the Ytterby quarry of Sweden. These ores are xenotime, euxenite, gadolinite, and monazite. Monazite river sand is... 

Rhenium was the last naturally occurring chemical element to be discovered in 1925 by Noddack, Tacke, and Berg in the mineral gadolinite. The name of this extremely rare element (the estimated occurrence in the earth s crust is about 0.7 ppb ) is derived from the Rhine river. Residues from the processing of molybdenum ores represent the main source of the metal. 

Dysprosium was discovered in 1866 by Boisbaudran. It occurs in the earth s crust associated with other rare earth metals. It is found in the minerals, xenotime YPO4, gadolinite, euxemite and monazite (Ce, La, Th)P04. The concentration of dysprosium in seawater is 0.9 ng/L and in the earth s crust 5.2 mg/kg. 

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