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H' at. wt. (natural) 1.007967
   at. wt. (H') 1.007822
   at. no. 1
   m.p. - 259.140C
   b.p. - 252.870C 
   density 0.08988 gm./l
   density (liquid) 70.8 gm/i. (-2530C)
   density (solid) 7016 gm/i. (-2620C)
   valence 1.
Electronic configuration
K L M N O P Q
1 2 3 4 5 6 7
s s p s p d s p d f s p d f s p d f s p d f
1            
HOLMIUM'('1. Holmia, for Stockholm), Hb; at. wt. 164.930; at. no.67; m.p. 1470"C; h.p. 2720~C; sp. gr. 8.781 (250C); valence + 3. The spectral absorption bands of holmium were noticed in 1878 by the Swiss chemists Delafontaine and Soret, wh9 announced the existence of an "Element X". Cleve, of Sweden, later independently dis- covered the element while working on erhia earth. The element is named after Cleve's native city. Pure holmia, the yellow oxide, was prepared by Homberg in 1911. Holmium occurs in gado/inite, monazite, and in other rare-earth minerals. It is commercially obtained from monazite, occurring in that mineral to the extent of about 0.05 %. It has been isolated in pure form only in recent years. It can be separated from other rare earths by ion-exchange and solvent extractiori techniques, and isolated by the reduction of its anhydrous chloride or fluoride with calcium metal. Pure holmium has a metallic to bright silver luster. It is relatively soft and malleable,, and is stable in dry air at room tem- perature, but rapidly oxidizes in moist air and at elevated temperatures. The metal has unusual magnetic properties. Few uses have yet been found for the element. The element, as with other rare earths, seems to have a low acute toxic rating. The price of 99+ % holmium metal is about $1 .50/gm. or 5500/lb.

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