Cerite-

Lanthanum is found in rare-earth minerals such as cerite, monazite, allanite, and bastnasite. Monazite and bastnasite are principal ores in which lanthanum occurs in percentages up to 25 percent and 38 percent respectively. Misch metal, used in making lighter flints, contains about 25 percent lanthanum. 

Gr. neos, new, and didymos, twin) In 1841, Mosander, extracted from cerite a new rose-colored oxide, which he believed contained a new element. He named the element didymium, as it was an inseparable twin brother of lanthanum. In 1885 von Welsbach separated didymium into two new elemental components, neodymia and praseodymia, by repeated fractionation of ammonium didymium nitrate. While the free metal is in misch metal, long known and used as a pyrophoric alloy for light flints, the element was not isolated in relatively pure form until 1925. Neodymium is present in misch metal to the extent of about 18%. It is present in the minerals monazite and bastnasite, which are principal sources of rare-earth metals. 

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. 

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. 

Praseodymium is the 41st most abundant element on Earth and is found in the ores of mona-zite, cerite, bastnasite, and allanite along with other rare-earths. Praseodymium is also the stable isotope resulting from the process of fission of some other heavy elements, such as uranium. 

Samarium is the 39th most abundant element in the Earths crust and the fifth in abundance (6.5 ppm) of all the rare-earths. In 1879 samarium was first identified in the mineral samarskite [(Y, Ce U, Fe) (Nb, Ta, Ti )Ojg]. Today, it is mostly produced by the ion-exchange process from monazite sand. Monazite sand contains almost all the rare-earths, 2.8% of which is samarium. It is also found in the minerals gadolmite, cerite, and samarskite in South Africa, South America, Australia, and the southeastern United States. It can be recovered as a byproduct of the fission process in nuclear reactors. 

Europium is the 13th most abundant of all the rare-earths and the 55th most abundant element on Earth. More europium exists on Earth than all the gold and silver deposits. Like many other rare-earths, europium is found in deposits of monazite, bastnasite, cerite, and allanite ores located in the river sands of India and Brazil and in the beach sand of Florida. It has proven difficult to separate europium from other rare-earths. Today, the ion-exchange... 

The element was discovered by Klaproth in 1803 and also in the same year by Berzelius and Hisinger. It is named after the asteroid Ceres. Cerium is found in several minerals often associated with thorium and lanthanum. Some important minerals are monazite, aUanite, cerite, bastnasite, and samarskite. It is the most abundant element among aU rare-earth metals. Its abundance in the earth s crust is estimated to be 66 mg/kg, while its concentration in sea water is approximately 0.0012 microgram/L. 

The element was discovered hy von Welshach in 1885 after he succeeded in fractionating ammonium didymium nitrate, thus splitting didymia into two new rare earths. Earlier, in 1841, Mosander extracted a rose-colored oxide from cerite, which he named didymium and which actually was a mixture of two rare earth elements. These two new elements were named hy von Welshach as praseodymia (green twin) and neodymia (new twin). 

Neodymium occurs in nature in the minerals hastnasite, monazite, cerite and allanite. The element always is associated with other rare earths, especially cerium group elements. Its abundance in the earth s crust is about 0.0024%. 

Terbium occurs in nature associated with other rare earths. It is found in minerals xenotime, a rare earth phosphate consisting of 1% terbia and in euxenite, a complex oxide containing about 1.3% terbia. It also is found in cerite, monazite, and gadolinite. Also, the element has been detected in stellar matter. Abundance of terbium in the earth s crust is estimated to be 1.2 mg/kg. 

J, J, Berzelius and his collaborator Wilheim Hisinger, isolated from a heavy mineral found in 1781 in a mine at Bastnas, Sweden, another similar and yet somewhat different "earth". This one was named ceria and the mineral cerite after the then recently discovered planetoid Ceres, It was believed at the time, that both yttria and ceria were single elements, but subsequent study showed each to be a mixture of oxides, the complete separation and identification of which required more than a century of effort. 

The mam object of Berzelius and Hisinger s analysis of cerite was to search for yttria, which might easily have escaped the attention of Scheele and de Elhuyar since it was unknown at the time their investigation was made (29). Although they failed to find yttria, Berzelius and Hisinger discovered instead the new earth ceria. ... 

Wilhelm Hisinger, 1766-1852. Swedish mineralogist and geologist. Owner of the famous Riddarhytta mining property in Vestmanland, where cerite was discovered. He was one of the first to analyze the lithium mineral petalite. 

Mine Head-Frame at Biddarhyttan. The mineral cerite was discovered there in 1751 by A. F Cronstedt. Georg Brandt, the discoverer of cobalt, was bom at Biddarhyttan. 

Ekeberg (40, 41), M. H Klaproth, and N.-L Vauquelin all investigated Gadolin s new oxide, and it came to be called ijttria, a name derived from Ytterby. In 1803 Klaproth discovered in the mineral cerite another earth which he called terre ochroitebut which is now known as ceria. Berzelius and Wilhelm Hisinger also discovered ceria independently, but upon further investigation neither their yttria nor their ceria proved to be a pure oxide (3). 

On August 30-Sept. 2, 1842, Berzelius wrote Theophile-Jules Pelouze concerning a meeting of Scandinavian naturalists which had been held in Stockholm Mr. Mosander announced a new metal, found with lanthanum in cerite, a metal which seems to accompany the cerium and yttrium wherever one finds them.. . The oxide of this metal, which... 

Mar. 17, 1803 1803 Birth of Carl Lowig, independent discoverer of bromine. Klaproth, Berzelius, and Hisinger analyze cerite and discover the earth ceria. 

Historically, the first rare earth specimen was found by K. A. Arrhenius near Ytterby in 1787. The Finnish Chemist, Johann Gadolin, in 1794, for the first time, successfully separated a new oxide from the mineral found by Arrhenius. This new oxide was named yttria by Ekebero (1797). The mineral was named gadolinite. In 1803 another oxide, very similar to yttria, was discovered independently by Klaproth, and Berzelius and Hisinger. This new oxide was named ceria, and the mineral from which it was isolated was called cerite. 

The Tuscany Magmatic Province (Fig. 2.1) comprises several mafic to silicic intrusive and extrusive centres scattered through southern Tuscany and the Tuscan archipelago. The silicic rocks of the Tolfa-Manziana-Cerite area, north-west of Rome, and a mafic ultrapotassic dyke from Sisco (Corsica) are also traditionally included into the Tuscany Province (Poli et al. 2003). 

Tolfa-Manziana-Cerite 3.5 - Multicentre complex made of trachydacite to rhyolite lava flows, domes and pyroclastic flows. 

Tolfa-Cerite + Vercelli seamount Torre Alfina O Capraia... 

Silicic volcanics occur as lavas at San Vincenzo, Roccastrada, Monte A-miata, Monti Cimini and Tolfa-Manziana-Cerite complex. Pyroclastic rocks are scarce or absent, and a few ignimbrites only occur at Monti Cimini and Cerite complex. Silicic intrusions crop out in the islands of Elba, Montecristo and Giglio, and at Campiglia and Gavorrano in southern Tuscany. Other granitoid bodies occur as seamounts in the northern Tyrrhenian Sea (e.g. Vercelli Barbieri et al. 1986) and as hidden intrusions in several places of southern Tuscany (e.g. Franceschini et al. 2000 Poli et al. 2003). 

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