holmium

holmium
    n 1: a trivalent metallic element of the rare earth group;
         occurs together with yttrium; forms highly magnetic
         compounds [syn: {holmium}, {Ho}, {atomic number 67}]
    

Holmium \Hol"mi*um\, n. [NL., from Stockholm.] (Chem.)
   A rare element of atomic number 67 said to be contained in
   gadolinite. Chemical symbol Ho. Atomic weight 164.93. Valence
   +3. It was detected by spectral absorption bands in 1878 by
   the Delafontaine and Soret, who called it "Element X". Later
   the Swedish chemist Cleve independently discovered it in
   erbia, and named it after his native city Stockholm. The
   first preparation of pure Holmia, the yellow oxide, was not
   made until 1911. --HCP61 -- {Hol"mic}, a.
   [1913 Webster +PJC]
    

holmium
Symbol: Ho
Atomic number: 67
Atomic weight: 167.26
Relatively soft and malleable silvery-white metallic element, which is
stable
in dry air at room temperature. It oxidizes in moist air and at high
temperatures. It belongs to the lanthanoids. A rare-earth metal, it is
found
in the minerals monazite and gadolinite. It possesses unusual magnetic
properties. One natural isotope, Ho-165 exists, six radioisotopes exist,
the
most stable being Ho-163 with a half-life of 4570 years. Holmium is used
in
some metal alloys, it is also said to stimulate the metabolism.
Discovered by
Per Theodor Cleve and J.L. Soret in Switzerland in 1879. The name homium
comes
from the Greek word Holmia which means Sweden. While all holmium
compounds
should be considered highly toxic, initial evidence seems to indicate
that
they do not pose much danger. The metal's dust however, is a fire
hazard.