Carl Auer von Welsbach was born in Septembeer 1858 In Vienna. He was a chemist and engineer with unique talent of understanding how to pursue fundamental science and, at the same time, of commercializing his discoveries in science into successful products. In other words he was both scientist and inventor.
He studied math, chemistry, physics and thermodynamics in technical University of Vienna and the University of Heidelberg. He started to work with chemical separation methods for investigations on rare earth elements in 1882. Auer developed a new method for separating Didymium, based on crystallisation of didymium ammonium nitrate solution. He gave the pink components the name Neodidymium (which was later changed to neodymium), and the green component, the name Praseodymium. In 1885 he produced the first incandescent mantle out of lanthanum oxide. In his original production that he patented in 1885, he used a mixture of 60%Ā magnesium oxide, 20%Ā lanthanum oxideĀ and 20%Ā yttrium oxide. These mantles which were also called āAuerlichtā gave off cold-greenish light and had a short length of use. Auer improved his production to stronger mantles with whiter lights by using a new mixture of 99%Ā thorium dioxideĀ and 1%Ā cerium dioxide. His new mantle was commercialized in 1892 and was quickly spread out in the streets of Europe. Meanwhile he developed a crystallization method for preparation of pure Thorium oxide. He also found the effect of the purity of the thorium oxide on its light emission.
Carl Auer von Welsbach was Robert Bunsenās student, and he had learned from him how to produce sparks from cerium by mechanical means. In 1903, he patented his pyrophoric cerium-iron alloy containing 70% cerium and 30% Iron for spark production.
In 1905 Auer wrote a report on the results of the spectroscopic analysis which showed Ytterbium is made up of two elements. He named the elements after Aldebaranium and Cassiopeium. He also tried to develop separation method based on the partial solubility of these elements oxalate. Moreover, he successfully performed large scale chemical separation of radioactive substances.
At that time Cerium was produced based on the electrolysis from the fused salts ( rare earth fluorides). He investigated the use of Cerit and Allenite minerals as source substances for the electrolysis. The production process of cerium was further improved by using Monazite and also the residues from the incandescent mantle production.
Beside the discovery of 4 rare earth elements Neodymium, Praseodymium, Ytterbium, and Lutetium, he also produced Ionium (known today as Thorium-230) .
Auer is particularly known for his discoveries and inventions on the rare earth metals, however he is also well known for production of metal filament light bulbs. His improvement in osmium filaments made the path towards the tungsten filament and the modern light bulb invention.
Carl Auer von Welsbach died on 1929 at the age of 70. His unique talents and qualities has ensured him a prominent lasting place both in science and industrial history.