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Responsible Investment in Mining and Exploration Stocks

Geology and ESG Research Analysis

 

           

 

Metals are part of our modern lives and we must think sustainability through a process: Extraction-Integration-Recycling.

Holmium

Name

Holmium

Symbol

Ho

Atomic number

67

Group

HREE

Subgroup

yttrium subgroup

Occurrence / Extraction

Present in monazite and gadolinite.
Extraction:  Pure holmium is obtained by reacting calcium metal with holmium fluoride (HoF3).

Use

Holmium is used in high strength magnets as a pole piece or magnetic flux concentrator. This magnetic property also has value in yttrium-iron-garnet (YIG) lasers for microwave equipment.

Holmium lasers at a human eye safe 2.08 microns allowing its use in a variety of medical and dental applications in both yttrium-aluminum-garnet (YAG) and yttrium-lanthanum-fluoride (YLF) solid state lasers. The wavelength allows for use in silica fibers designed for shorter wavelengths while still providing the cutting strength of longer wave length equipment.

Properties

Holmium has the highest magnetic moment (10.6µB) of any naturally occurring element. Because of this it has been used to create the highest known magnetic fields by placing it within high strength magnets as a pole piece or magnetic flux concentrator. Holmium is a silvery metal that is soft, ductile, and malleable.

Atomic mass: 164.93  g.mol -1
Electronegativity according to Pauling:  1.2
Density:  8.78 g.cm-3 at 20°C
Melting point: 1470°C
Boiling point:  2720 °C
 
The origin of the name comes from the Greek word Holmia meaning Stockholm.

Relative abundance

The abundance of holmium in the Earth's crust is estimated to be about 0.7 to 1.2 parts per million. It is less common than most other rare earth elements, but more common than iodine, silver, mercury, and gold.

atomic mass (g.mol -1)

164.93

density (g/cm3)

8.8

Oxydation number

  +3

Melting point (°C)

1470

Boiling point (°C)

2720

Magnetic moment

 

Abundance in the Earth's crust ( ppm)

0.78

discovery

Per Theodore Cleve  in 1879