# Victor Goldschmidt

Victor Moritz Goldschmidt ForMemRS (27 January 1888 – 20 March 1947) was a Norwegian mineralogist considered (together with Vladimir Vernadsky) to be the founder of modern geochemistry and crystal chemistry, developer of the Goldschmidt Classification of elements.

## Early life and education

Goldschmidt was born in Zürich, Switzerland on 27 January 1888.$^{:7}$ His father, Heinrich Jacob Goldschmidt, (1857–1937) was a physical chemist at the Eidgenössisches Polytechnikum and his mother, Amelie Koehne (1864–1929), was the daughter of a lumber merchant. They named him Viktor after a colleague of Heinrich, Victor Meyer. His father's family was Jewish back to at least 1600 and mostly highly educated, with rabbis, judges, lawyers and military officers among their numbers. As his father's career progressed, the family moved first to Amsterdam in 1893, to Heidelberg in 1896, and finally to Kristiania (later Oslo), Norway in 1901, where he took over the physical chemistry chair at the university. The family became Norwegian citizens in 1905.
Goldschmidt entered the University of Kristiania (later the University of Oslo) in 1906 and studied inorganic and physical chemistry, geology, mineralogy, physics, mathematics, zoology and botany. He secured a fellowship for his doctoral studies from the university at the age of 21 (1909). He worked on his thesis with the noted geologist Waldemar Christofer Brøgger and obtained his Norwegian doctor’s degree when he was 23 years old (1911). For his dissertation titled Die Kontaktmetamorphose im Kristianiagebiet ("The Contact Metamorphism in the Kristiania Region"), the Norwegian Academy of Sciences awarded him the Fridtjof Nansen award in 1912. The same year he was made Docent (Associate Professor) of Mineralogy and Petrography at the university.

## Career

In 1914 Goldschmidt applied for a professorship in Stockholm and was offered the position. To entice him to stay, the University of Kristiania persuaded the government to establish a mineralogical institute with a professorship for him.$^{:19}$ In 1929 Goldschmidt was appointed the chair of mineralogy in Göttingen, and he hired Reinhold Mannkopff and Fritz Laves as his assistants.$^{:54,58}$ However, after the rise of the Nazis to power, he became unhappy with the treatment of non-Aryans like himself (although the university treated him well) and he resigned in 1935 and returned to Oslo.$^{:21}$ In 1937, he was invited by the Royal Society of Chemistry to give the Hugo Müller lecture.
On 9 April 1940 the Germans invaded Norway. On 26 October 1942 Goldschmidt was arrested at the orders of the German occupying powers as part of the persecution of Jews in Norway during World War II. Taken to the Berg concentration camp, he became seriously ill and after a stay in a hospital near Oslo, he was released on 8 November, only to be rearrested on 25 November. However, as he was on the pier and about to be deported to Auschwitz, he was freed because some colleagues had persuaded the chief of police that his scientific expertise was essential to the state.$^{:22}$ Goldschmidt soon fled to Sweden.$^{:23}$
Goldschmidt was flown to England on 3 March 1943 by a British intelligence unit, and provided information about technical developments in Norway. After a short period of uncertainty about his future status, he was assigned to the Macaulay Institute for Soil Research (in Aberdeen) of the Agricultural Research Council. He participated in discussions about the German use of raw materials and production of heavy water. He attended open meetings in Cambridge, Manchester, Sheffield, Edinburgh and Aberdeen and lectured at the British Coal Utilisation Research Association on the presence of rare elements in coal ash.$^{:24}$ His British professional associates and contacts included Leonard Hawkes, C E Tilley and W H Bragg, J D Bernal, Dr W G (later Sir William) Ogg.$^{:18,24}$
Goldschmidt moved from Aberdeen to Rothamsted, where he was popular and nicknamed ‘Goldie’. However, he wanted to go back to Oslo – not welcomed by all Norwegians – and returned there on 26 June 1946, but died soon after, at age 59.$^{:26}$

## Scientific work

For his thesis, Goldschmidt studied the Oslo graben, a valley formed by the downward displacement of a block of land along faults on each side. The region had recently been mapped by Brøgger. In the Permian, magmas intruded into the older rocks, heating the surrounding rock. This resulted in mineralogical changes known as contact metamorphism, resulting in a fine-grained class of rocks known as hornfels. Goldschmidt made a systematic study of the hornfels. He showed that, of the minerals to be found in the hornfels, only certain associations occurred. For example, andalusite could be associated with cordierite but never with hypersthene.$^{:13–14}$
From his data on the hornfels, Goldschmidt deduced a mineralogical phase rule. It is a special case of the Gibbs' phase rule for phases in thermodynamic equilibrium with each other, which states that
    $C-P=F-2,$
where C is the minimum number of chemical components, P is the number of phases, and F is the number of degrees of freedom (e.g., temperature and pressure) that can vary without changing C or P. As an example, the chemical compound Al$_2$SiO$_5$ can occur naturally as three different minerals: andalusite, kyanite and sillimanite. There is a single component (C = 1), so if all three minerals coexist (P = 3), then F = 0. That is, there are no degrees of freedom, so there is only one possible combination of pressure and temperature. This corresponds to the triple point in the phase diagram.$^{:15–16}$
If the same mineral association is found in several rocks over some region, it must have crystallized at a range of temperatures and pressures. In that case, F must have been at least 2, so
    $C\geq P.$
This expresses Goldschmidt's mineralogical phase rule: the number of phases is no greater than the number of components.
In the early 20th century, Max von Laue and William L. Bragg showed that X-ray scattering could be used to determine the structures of crystals. In the 1920s and 1930s, Goldschmidt and associates at Oslo and Göttingen applied these methods to many common minerals and formulated a set of rules for how elements are grouped. Goldschmidt published this work in the series Geochemische Verteilungsgesetze der Elemente [Geochemical Laws of the Distribution of Elements].$^{:2}$