Escutcheons of Science
 Johan Gadolin (1760-1852)

Johan Gadolin (1760-1852)
Finnish chemist who discovered Yttrium, in 1792.

The above is a copyrighted picture reproduced here by permission.  © 2008   by Jochen Wilke.
Swedish blazon kindly provided by  Anders Segersven  from 
Granfelts Vapenbok  ("Finlands Ridderskaps och Adels Vapenbok", Helsinki/Helsingfors 1888).

Shield :  Argent, a bend Azure charged with two mullets Or
between a rose Gules in chief and a bunch of crystals [of gadolinite?] Proper in base.
Crowned helmet ;  three ostrich feathers Argent on a laurel wreath Vert.
Mantling :  Azure, doubled Sable.   [ Two cannons in saltire under the shield. ]

Vapnet :  En sköld af silfver fält med en blå balk, belagd med två femuddiga gyllene stjärnor,
samt sidosatt, å vänster en chef med en röd ros å höger med en stuff kristaller  ("gadolinit"?).
Krönt hjälm ;  tre hvita plymer ur en grön lagerkrans.
Hjälmtäcke  blått, af svart foder.   [ Under skölden korsvis två kanoner. ]

The family of Johan Gadolin is registered under number 245 in the Finnish  House of Nobility  (Riddarhuset).
It's distinct from a related (extinct) Gadolin family which bore slightly different arms and was registered under number 180.

 245. Gadolin 
 (Granfelts Vapenbok)

The chemist  Johan Gadolin  (1760-1852) was born in Turku, Finland.  His father, Jakob Gadolin (1719-1802)  was Professor of Physics at the University of Turku  (founded in 1640)  and would soon become Professor of Theology (1662) and finally, in 1788, Bishop of Turku  (Turku was the oldest diocese in Finland; it had become Lutheran at the time of the Reformation).  Apparently, the paternal grandfather of Johan, also named Jakob, was a Lutheran minister himself who had taken on the surname  Gadolin  from the Hebrew word  gadol  ("great").

On the maternal side, the grandfather of Johan Gadolin was  Johan Browallius (1707-1755) Professor of Botany at the University of Turku and a good friend of Linnaeus (1707-1778).  He also served as Lutheran Bishop of Turku from 1749 to 1755  (about 40 years before his son-in-law would hold the same office).

In 1792,  Johan Gadolin  analyzed samples of a mineral which had been discovered by Lieutenant Arrhenius in 1788, next to the Swedish village of Ytterby, near Stockholm  (that mineral would be named gadolinite in 1800).  In it, Gadolin found a new substance which he called "ytterbia" at first, but the name was shortened to  yttria  in 1797, by the deaf Swedish chemist  Anders Gustaf Ekeberg  (1767-1813) as he repeated Gadolin's experiments at Uppsala  (Ekeberg would later be credited with the discovery of  tantalum (73)  in 1802).  Gadolin's  yttria  turns out to be (mostly) an oxide of the first  rare earth  element ever discovered, which we now call  yttrium  (Z=39, Symbol: Y).  Gadolin himself obtained  yttrium trihydroxide  shortly thereafter.  He published his discoveries about  yttria  in 1794.  At first,  yttria  itself was thought to be an element, but it proved to be the  oxide  of a new element, as shown by  Humphry Davy (1778-1829) in 1808...

Rare-earth elements  are simply, by definition, the elements in the third column of the Periodic Table  (4 "boxes" which span a total of 32 elements, including the 15 lanthanides and the 15 radioactive actinides).  Almost half of the  68  transition metals  [below element 112]  are  rare earths.

Several rare-earth elements besides  yttrium  (39)  can be found in gadolinite.  The lightest of them is  scandium (Z=21) which was discovered in 1879 by the Swedish chemist Lars Fredrik Nilson (1840-1899)  who extracted its oxide  (scandia)  from both gadolinite and euxenite.  Nilson suspected that  scandium  was actually the hypothetical  ekaboron  predicted in 1869  by Mendeleev...  This was confirmed shortly thereafter by the Swedish chemist Per Theodor Cleve (1840-1905)  the father of Astrid Cleve von Euler (1875-1968)  and grandfather of Ulf von Euler (1905-1983; Nobel 1970).

Gadolinium (64) is another rare earth  (a lanthanide)  which can be found in some samples of gadolinite, although extraction from monazite or bastnäsite seems commercially more important nowadays.  Uniquely, this is a metal which is strongly ferromagnetic  (like iron)  in the Winter but looses its ferromagnetic properties in hot weather.  Indeed, its  Curie temperature  happens to be very close to room temoerature  (it's listed as  293.2 K,  which is about  20°C  or  68°F).  Gadolinium  was discovered in its oxidized form  (gadolinia)  in 1880 by the Swiss chemist Jean Charles Galissard de Marignac (1817-1894).  The metal itself was isolated in 1885 by Lecoq de Boisbaudran (1838-1912)  the prolific French chemist who discovered gallium (31) in 1875, samarium (62) in 1880, and dysprosim (66) in 1886...

Both the  gadolinium  metal and its oxide  (gadolinia)  were indirectly named after Johan Gadolin, simply because the key mineral  (which Gadolin had worked on in 1792)  had been known as  gadolinite  since 1800.

Wikipedia   |   Grandfather of Gadolinium (pdf)


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