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Geology and ESG Research Analysis

 

           

 

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

Thulium

Name

Thulium

Symbol

Tm

Atomic number

69

Group

HREE

Subgroup

yttrium subgroup

Occurrence / Extraction

It occur in monazite, euxenite, and gadolinite.

Extraction:  as many lanthanides, pure thulium is made by treating its fluorine compound with calcium.

Use

Thulium is mainly used in making crystal and lasers. Lasers containing thulium are used in satellites that take pictures of the Earth. (Intelsat VI). 

An important application of the thulium in the Medicine area, and relatively independent of its high cost, is the production of portable X-ray sources. These sources are available for about one year, as tools in medical and dental diagnosis, as well as to detect defects in mechanical and electronic inaccessible components. This type of sources does not need excessive protection. Usually a small cap of lead is enough.

 Thulium can also be used in magnetic and ceramic materials (ferrite), similar to the yttrium-iron alloys, nowadays used in the microwave technologies.

Properties

Thulium is a silvery metal so soft it can be cut with a knife. It is easy to work with and is both malleable and ductile. Thulium is relatively stable in air and reacts slowly with water and more rapidly with acids.

Atomic mass: 168.93  g.mol -1
Electronegativity according to Pauling:  1.2
Density:  9.31 g.cm-3 at 20°C
Melting point: 1545 °C
Boiling point:  1950 °C
 
Named after Thule, an ancient name for Scandinavia.

Relative abundance

Thulium is probably the rarest of the lanthanide elements. Its abundance is estimated at about 0.2 to 1 part per million in the Earth's crust. This still makes it more abundant than silver, platinum, mercury, and gold.

atomic mass (g.mol -1)

168.93

density (g/cm3)

9.31

Oxydation number

  +3

Melting point (°C)

1545

Boiling point (°C)

1950

Magnetic moment

 

Abundance in the Earth's crust ( ppm)

0.32

discovery

Theodore Cleve (SE) in 1879.