Minerals cerite

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. 

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). 

Wilhelm Hisinger, Jons Jacob Berzelius, Stockholm Cerite. Cerium 1803 The mineral cerite found in Bastnaes... 

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. 

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. 

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. 

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. 

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. 

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. 

Lanthanide chemistry started in Scandinavia. In 1794 Johann Gadolin succeeded in obtaining an earth (oxide) from a black mineral subsequently known as gadolinite he called the earth yttria. Soon afterwards, M.H. Klaproth, J.J. Berzelius and W. Hisinger obtained ceria, another earth, from cerite. However, it was not until 1839-1843 that the Swede C.G. Mosander first separated these earths into their component oxides thus ceria was resolved into the oxides of cerium and lanthanum and a mixed oxide didymia (a mixture of the oxides of the metals from Pr through Gd). The original yttria was similarly separated into substances called erbia, terbia, and yttria (though some 40 years later, the first two names were to be reversed ). This kind of confusion was made worse by the fact that the newly discovered means of spectroscopic analysis permitted misidentifications, so that around 70 new elements were erroneously claimed in the course of the century. 

More than a century earlier, a heavy new mineral had been found near the town of Bastnas, Sweden, and given the name cerite. 

One rock contained a mineral that had never been seen before, cerite. Cerite was first discovered in 1803. The last new element found in cerite was not identified until almost a century later, in 1901. In 1880, French chemist Jean-Charles-Galissard de Marignac (1817—1894) was studying a new material found in cerite called samaria. Earlier chemists had identified samaria as a new element. 

Mosander had been educated as a physician and a pharmacist. In the early 1830s, he was put in charge of the minerals collection at the Stockholm Academy of Sciences. He became very interested in two minerals that had been discovered in Sweden many years before, yttria and cerite. He devoted much study to the composition of these two minerals. 

As with other rare earth elements, the primary sources of samarium are the mineral monazite and bastnasite. It is also found in samarskite, cerite, orthite, ytterbite, and fluorspar. 

Terbium occurs with other lanthanoids in minerals such as monazite, cerite, gadolinite, xenotime, and euxenite. In 2007, terbium oxide sold for about 850 per kilogram. 

The lanthanides can be found in the earth s crust at a wide range of concentrations. For example, thulium is present at only 0.5 ppm, whereas lanthanum and cerium are present at 30 and 60 ppm, respectively. The mineralized forms of the lanthanides that are of greatest commercial and mining interest are mon-azite, bastnaesite, and cerite. The most common commercial forms of the lanthanides are the oxides and carbonates, which have low solubility and mobility. In contrast, the lanthanide chlorides, nitrates, and acetates, because of their high solubility, are more likely to leach into groundwater and surface water. 

The mineral now known as cerite was discovered in 1751, but nothing unusual was observed concerning it until 1803, when Klaproth discovered that it gave an oxide resembling Ekeberg s yttria quite closely. Berzelius and Hisinger made a similar observation simultaneously and the names ceria and cerite were proposed for the oxide and mineral respectively. These names were derived from the planetoid Ceres which was then newly discovered. 

Lanthanum. La at. wt 138,9055 at. no. 57 valence 3. A rare earth metal. Two naturally occurring i 0-ropes 159La <99.911 %) La (0.089%) IJ La is radioactive, 1-12 X 1011 years artificial radioactive isotopes 125-137 140-144. Estimated abundance in earth s crust 5-1 ppm. Found in association with cerium and other light Ian-thanons. Minerals of commercial interest are monazite bastnaesite and cerite. Discovery and isoln Mosander ... 

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