Yttrium, atomic weight of, ~211~ detection of, ~212~ group, history of, ~194~ separation of, ~195~ history of, 194, ~208~ salts of, ~210~ separation of, ~196~, 205 Yttrocerite, 28, ~88~ Ythrocrasite, 28, 56 Ythrofluirite, 28, ~89~ Yttrofluorite, 28, ~89~ Yttrogarnet, 28, 45 Yttrogummite, 28, 49 Yttroilmenite, 60 Yttrotantalite, 29, 62 Yttrotitanite, 18, ~52~ Zircon, 29, 38, 45, ~47~, 90, 107 Zirconia, uses of, ~323~ Zirconium, atomic weight of, ~249~ compounds of, ~249~ detection of, ~242~ estimation of, ~250~ extraction of, ~239~ group, relations of, ~219~, 240 history of, ~238~ industrial applications of, ~321~ Zirkelite, 29, 79 PRINTED BY SPOTTISWOODE AND CO. LTD., COLCHESTER LONDON AND ETON Transcriber’s Notes Inconsistent and unusual spelling and hyphenation (including those of proper and geographical names) have been retained, except as mentioned below. Depending on the hard- and software used and their settings, not all elements may display as intended. Lists of elements were printed both with and without separating commas (for example, R´´ = Ca, Fe´´, Be and R´ = NH₄,K,Rb,Cs); these have not been standardised. Pages 34, weighing 200 lb.: later (page 41) referred to as weighing 300 lb. Some tables appear to use nm, others Å; this has not been standardised. Page 181, table: 5923·35 may be an error; it is out of sequence. Page 200, table: 379·5 may be an error; it is out of sequence. Page 236, (NH₄)₂O₂,TiO₃,H₂O₂: as printed in the source document; the final O₂ is probably an error. Changes: Footnotes have been moved to under the paragraph in which they are referenced; illustrations have been moved out of text paragraphs. Some obvious minor typographical and punctuation errors have been corrected silently. Moh’s scale has been changed to Mohs’ scale, Guèrin and Guérin to Guérin. Where there was a space between the number and the percent sign, or between the degree sign and the C, this has been deleted for the sake of consistency. Page vii: Blomstandine changed to Blomstrandine. Page 20, Monazite: Yttr = 1 4; changed to Yttr = 1-4; Page 26: Osterby changed to Österby. Page 46: Struverite changed to Strüverite as elsewhere. Page 87: Kraus and Heitinger changed to Kraus and Reitinger. Page 155: Footnote anchor [194] was missing in the source document, and has been inserted at the end of the paragraph. End of the Project Gutenberg EBook of The Rare Earths, by S. I. Levy