The Rare Earths: Their Occurrence, Chemistry, and Technology

in 1804 (see under Cerite, p. 32). The classical work of Mosander, carried out between 1838 and 1842, showed the complex nature of the new oxides. From ceria he separated three...

The oxide zirconia was isolated as a new earth from zircon from Ceylon by Klaproth in 1789; six years later the new earth was obtained also from hyacinth, the gem-variety of the...

In his examination of the ‘Yttria’ of Gadolin and Ekeberg, during the years 1839 to 1843, Mosander, by methods based on differences in strength of the oxides as bases, separated...

Though probably at least as plentiful in nature as most of the common metals, titanium has always, until quite recently, been regarded as one of the rare elements. Of its chemis...

~Cerite.~--Cerite is a silicate of the cerium metals, with small amounts of lime, ferrous oxide and water. Hintze gives the formula H₃(Ca,Fe)Ce₃Si₃O₁₃,[15] which Groth interpret...

The history of the rare earth minerals begins in the year 1751, when the Swedish mineralogist Cronstedt described a new mineral, which he had found intimately mixed with chalcop...

The oxides zirconia and thoria were generally classed among the rare earths by the earlier chemists. This view was based partly upon the mode of occurrence of the oxides, which...

commerce. Small quantities are obtained from thorianite, the separation of the pure material presenting, in this case, very little difficulty by reason of the solubility of the...

In his examination of the ceria earths in 1839, Mosander discovered a new constituent, which he called Lanthana; the new oxide was removed in solution when the ignited mixture w...

The chemist who sets out to prepare a pure compound of a rare earth element is faced by a great difficulty. The rare earth compounds occur in nature, as one might expect from th...

The technical uses of the members of this group of the elements we are considering, apart from the employment in the manufacture of incandescent mantles, are at present very res...

The history of the artificial silk industry, since its foundation about the year 1890, illustrates curiously the rapidity with which isolated facts, of apparently merely academi...

The extraction of the rare earth elements from minerals, by which they are obtained in the form of the oxalates, and the methods of bringing these into solution, have already be...

In the present chapter no attempt will be made to give a complete account of all the phenomena of radioactivity which have been observed in the mineral world. There are, however...

[59] In this and all similar minerals, columbium (niobium) and tantalum are to be regarded as vicarious; they replace each other in all proportions. It seldom happens that a pur...

The fabric chosen for the manufacture of the original Welsbach mantles was a specially selected cotton, woven from threads of a specified thickness. The oxide skeleton left afte...

The group of elements which we are considering can be divided, from the point of view of technical application, into two classes. The first of these contains one element only, t...

In his examination of the yttria earths in 1842, Mosander described two new oxides isolated from the old yttria. To one of these, an orange-yellow earth which yielded colourless...

~Uraninite~ or Pitchblende.--Uraninite consists essentially of oxides of uranium (UO₂ + UO₃ = 75 to 85 per cent.), associated with thoria, zirconia, rare earths, beryllia, and o...

It has been stated that monazite is a not uncommon accessory constituent of many rocks, particularly of granites, gneisses, diorites, etc. The crystalline material, of which an...

~Monazite~, Phosphocerite.--Monazite, by far the most important, commercially, of all the rare earth minerals, is essentially an orthophosphate of the ceria earths, of the formu...

~Yttrotitanite or Keilhauite.~--A titano-silicate of calcium, aluminium, iron and yttrium metals. The mineral is isomorphous with titanite, CaO,TiO₂,SiO₂ (_q.v._), and is itself...

The mysterious group of substances to which have been given the title of “rare earths” has long been the subject of my special study, and no one knows better the magnitude of th...

It has been stated in the previous chapter that the first Auer mantles were made of mixtures of various rare earth oxides, the mixture of thoria with 1 per cent. of ceria being...

The chemistry of the rare earth elements begins in the year 1794, with Gadolin’s discovery of the new oxide ‘Ytterbia,’ for which the name Yttria was subsequently proposed by Ek...