Cronstedt, Axel Fredrik

(b. Turinge, Sweden, 23 December 1722; d. Säter, sweden, 19 August 1765)

chemistry, mineralogy.

Following in his father’s footsteps, Cronstedt studied mathematics at Uppsala and prepared to become a fortifications officer. He changed his mind, however, when, through Johan Wallerius and Sven Rinman, he became interested in mineralogy. He attended the Bergs-Kollegium in 1742 as an observer; there he attracted the attention of Daniel Tilas, a leading figure in mining and metallurgy, who was to have a decisive influence on his further education included field study in various aspects of mining.

Between 1741 and 1743, when Sweden was at war with Russia, Cronstedt had to serve in the army; part of his service was as secretary to his father, who was a general and head of the Corps of Engineers. It was only toward the end of 1743 that he was able to make the first of many trips to the mines and smelting works, to observe the methods in use. These trips, together with his thorough inquiry into, among other things, the metallurgy of silver, lead, and copper, made Cronstedt a first-rate mining expert. He recorded his experiences and observations in reports and papers that he presented to the Bergs-Kollegium and to the Swedish Academy of Science. To supplement this emphasis on the practical side of his education, in 1746 he took a course in “the art of experiment and chemistry”; he continued the course for several years, with occasional interruptions. His teacher was Georg Brandt, the discoverer of cobalt.

In January 1748, Cronstedt was made a director of the East and West Bergslagen, a large area in the richest ore-bearing region of central Sweden. Among his duties was the supervision of the silver works at the Skiss foundries in southern Dalarna (Kopparbergs län), which had an excellent laboratory for testing metals and minerals. Here Cronstedt found a quiet place where, undisturbed, he could devote himself to his chemical and mineralogical research and experiments. Especially fruitful was his work on “coppernickel” (niccolite) obtained from the cobalt mines at Los, in Hälsingland. Both Urban Hiärne and Wallerius had declared “copper-nickel” to be a mixture of cobalt, arsenic, copper, and iron. That the ore contained copper seemed evident, since its solution in nitric acid was green, turning to blue upon treatment with ammonia. But when Cronstedt tested copper precipitates with iron or zinc, this did not occur. In another experiment the mineral withstood a humid atmosphere and, after calcination or reduction with the black flux of the lime that was formed, yielded a regulus, yellowish on the outside, with a silver-white metallic broken surface and slight magnetic properties. Since none of the then known metals, alone or in any of its compounds, possessed these properties, Cronstedt felt entitled to claim that he had found a new metal. His results were confirmed by the distinguished director of the Ädelfors placer mines, Henrik Theophilus Scheffer, an assayer and chemist renowned for his knowledge and skill.

Cronstedt further verified his discovery by showing that he could obtain his new metal not only from Swedish ore but also from Freiberg “copper-nickel.” His first report on his discovery appeared in the Kungliga Vetenskapsakademiens Handlingar for 1751, but not until a paper in the Handlingar for 1754 did he give his new metal a name, calling it “nickel,” after the material from which it was obtained, called “copparnickel” in Swedish. Most contemporary chemists acknowledged Cronstedt’s claim that he had discovered a new metal, but some, such as Balthazar Sage, Antoine Monnet, J. H. von Justi, and G. A. Scopoli, held to the old view represented by E. H. von Henckel and J. A. Cramer: that “copper-nickel” consisted of cobalt, iron, arsenic, and copper and that its regulus did not, in consequence, represent any new metal but was only a compound of previously known ones. It was not until Torbern Bergman’s dissertation De niccolo, defended in 1775 by Johan Afzelius, that Cronstedt’s claim was conclusively accepted.

In a number of other papers appearing in the Handlingar, Cronstedt published, among other things, his experiments on new types of iron ore (1751). Here he mentioned a mineral possessing an unusually high specific gravity, which he named “Bastnäs’ tungsten”; this led to other important discoveries. In 1803 Berzelius and Hisinger, at the same time as Klaproth, discovered that this substance was a water-containing silicate of a new metal that they named “cerium.” The ore, which they called “cerite,” was the substance in which Mosander later discovered didymium and lanthanum. Cronstedt reported on other series of experiments: with gypsum (1753), with the mineral that he roasted over a blowpipe flame and named “zeolite” (1756), and with the platina of Pinto(1764).

His discovery of nickel made Cronstedt known in the learned world, and his membership in the Royal Academy of Science and his further work assured his reputation as a scientist. His experiments, oriented toward the chemistry of metals, enabled him to gain an unprecedented insight into the inner structure of minerals. When this insight was combined with a clear understanding of his findings as a basis for a rational mineral system, it revealed the errors in earlier methods of classification. This prompted Cronstedt to publish anonymously his Försök til mineralogie, eller mineralrikets upställning (1758). In this essay he sought to lay the foundations for a new mineralogical system. Here, for the first time, he established the correct distinctions between simple minerals and rock minerals consisting of a mixture of several minerals. Since he thereby excluded the rock minerals from mineralogy as such, he also excluded fossil material, concretions and the like. In an appendix to Försök he published a classification of rocks. The work attracted considerable attention; and after it was translated into German in 1760, it quickly became known outside Sweden. Abraham Gottlob Werner, the world-famous mineralogist in Freiberg and the reformer of mineralogy, paid him due homage; and Berzelius declared him to be the founder of chemical mineralogy. In this connection it must be pointed out that even if other investigators had previously used the blowpipe in their tests, nobody before Cronstedt had so methodically applied this tool to the examination of minerals. Thus, he is entitled to be considered the actual founder of systematic blowpipe analysis.

BIBLIOGRAPHY

I Original Works. The library of the Academy of Science in Stockholm has a collection of Cronstedt’s writings, including 15 vols. of MSS, letters, transcripts, and other material.

His published works include “Rön och försök gjorde med trenne järnmalms arter,” in Kungliga Svenska Vetenskapsakademiens Handlingar, 12 (1751), 226–232; “Rön och försök gjorde med en malm-art, från Los kobolt-grufvor i Färila socken och Hälsingeland,” ibid.,287–292; “Rön och anmärkningar om gips,” ibid.,14 (1753), 44–47; “Fortsättning af rön och försök, gjorde med en malm-art fran Los kobolt-grufvor,” ibid.,15 (1754),38–45; Inträdes-tal om medel til mineralogiens vidare förkofran (Stockholm, 1754); “Rön och beskrifning om en obekant bärg art, som kallas zeolites,” in kungliga Vetenskapsakademiens Handlingar, 17 (1756),120–123; Försök til mineralogie, eller mineralrikets upställning(Stockholm,1758), trans. into German as Versuch einer neuen Mineralogie, by G. Wiedemann (Copenhagen, 1760); trans. into English, with notes, by Gustav von Engeström, as An Essay Towards a System of Mineralogy(London, 1770), with an appendix by M. T. Brunnich (London, 1772); 2nd ed., rev. and enl. by John Hyacinth de Magellan, 2 vols. (London, 1788); Cronstedts Versuch einer Mineralogie, vermehret durch Brünnich(Copenhagen-Leipzig, 1770); Essai d’une nouvelle minéralogie, trans. by M. Dreus fils (paris,1771); Saggio per formare un sistema de mineralogia, trans. by Angelo Talier (Venice. 1775; new ed., 1779); trans. into Russian by Matheus Kardiman (St. Petersburg, 1776); Axel von Kronstedts Versuch einer Mineralogie. Aufs neue aus dem Schwedischen übersetzi and vermehret von Abr. Gottlob Werner, I, pt.l (Leipzig, 1780); “Rön och anmärkningar vid jämtlands mineralhistoria,” ibid.,24 (1763), 268–289; “Några rön och anmärkningar vid platina di pinto,” ibid.,25 (1764), 221–228; Axel Friedrichs von Cronstedt Mineralgeschichte über das westmanländische and dalekarlische Erzgebirge, auf Beobachtungen and Untersuchungen gegründet, trans. by J. G. Georgi, notes by D. J. C. D. Schreber (Nuremberg, 1781);his autobiography, “Bergmästren A. F. Cronstedts egenhändiga lefnadsbeskrifning,” in Blad för bergshanteringens vänner inom örebrolän,5 (1886–1888), 99–116.

II. Secondary Literature. On Cronstedt or his work, see J. Landauer, “Die ersten Anfänger der Löthrohranalyse,” in Berichte der Deutschen Chemischen Gesellschaft,26 (1893), 898–908; S. Rinman, Åminnelsetal öfver Axel Fredrik Cronstedt, hållet den 6 mars 1766 (Stockholm, 1766); and Nils Zenzén, in Svenskt biografiskt lexikon, IX (Stockholm, 1929), 279–295.

Uno Boklund