X. On scandium.—Part II

Abstract

Since the publication of the first part of my paper on Scandium, G. Eberhard, of the Astrophysical Observatory, Potsdam, reasoning from the fact that the strongest lines of the scandium spectrum are observed in the spectra of stars in diverse stages of development, has come to the conclusion that scandium must be universally distributed on the earth. Investigating the arc spectra of 366 minerals and rocks, he obtained the remarkable result that scandium in small quantities is actually one of the most widely distributed earth elements. He shows that it occurs most frequently in zirconium minerals—in beryls, titanates, columbites, and titanocolumbites of the rare earths—also in micas; and, finally, that specimens of wolframite and tinstone from Saxony and Bohemia contain scandium in sufficient quantity to make its extraction advantageous. These results of Eberhard were quickly verified by Prof. R. J. Meyer, Berlin University, who, in a preliminary paper, has described experiments on extracting scandia from the Zinnwald wolframite. Prof. Meyer concludes that this wolframite contains from 0·14 to 0·16 per cent, of rare earths, and that these rare earths contain 0·30 to 0·33 per cent, of scandia. Thus the original wolframite would contain about 0·15/100 x 0·315 /100 = 0·04725/10000, or about 0·0005 per cent, of scandia. Prof. Meyer has worked out two methods of separating scandia from the wolframite rare earths :—( a ) Precipitation with hydrofluoric acid from an intermediate product in which the scandium has been concentrated by an oxalic acid precipitation, and ( b ) precipitation with hydrofluosilicic acid, or sodium silicofluoride in acid solution.