Dysprosium oxalate

Figure 4. Precipitation of dysprosium from simulated waste as a function of oxalate ion concentration...

The lutetium hahdes (except the fluoride), together with the nitrates, perchlorates, and acetates, are soluble in water. The hydroxide oxide, carbonate, oxalate, and phosphate compotmds are insoluble. Lutetium compounds are all colorless in the solid state and in solution. Due to its closed electronic configuration (4f " ), lutetium has no absorption bands and does not emit radiation. For these reasons it does not have any magnetic or optical importance, see also Cerium Dysprosium Erbium Europium Gadolinium Holmium Lanthanum Neodymium Praseodymium Promethium Samarium Terbium Ytterbium. 

Let us now leap forward in time to be able to close the matter of the division of erbium. Lecoq de Boisbaudran developed a fantastically intricate and wearisome method for the separation of gadolinite rare earth elements, consisting of 32 precipitations with ammonia and 26 subsequent precipitations with oxalate, separation of the fractions and their spectroscopic and fluorescence studies. In 1886, he came to the conclusion that holmium is not homogeneous either, it contains another element which he named dysprosium. This element was apparently accepted by the chemists of the world without the usual unbelief and debate (Lecoq de Boisbaudran 1886). 

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