25
Bergman’s Contributions
to Mineralogy
As the majority of Swedish chemists up to the mid-nineteenth century, Bergman
had a natural interest in mineralogy. In fact, due to the influence of the Board of
Mines, he had to develop such an interest. This interest resulted in several papers on
mineral analysis (Chap. 23) and two works on classification of minerals. To his
help, Bergman had his extensive mineral collection (Sect. 9.4), but he also made
several trips through Sweden during the summers to visit mines and other places of
mineralogical interest. He also received mineral samples from colleagues around
Europe. Since Bergman’s analytical methods were discussed in Chap. 23, this
chapter will focus on his analytical results and conclusions.
25.1 Semi-precious Stones and Gems
The October to December issue of the Transactions of 1777 featured a series of five
papers in a row on a mineral called Oculus mundi (world’s eye), now called
hydrophane and recognised as a rare variety of opal. The last of these papers,
Tilläggning om Oculus mundi [1] (addition on Oculus mundi), was written by
Bergman. Bergman’s addition to the discussion on this mineral was whether it was
properly classified as an opal or carnelian. Bergman also used hydrochloric acid
(Acidum salis) to extract aluminium (earth of alum) from Oculus mundi.
In his 1766 paper on the electrical properties of tourmalines (Sect. 5.2), Bergman
did not discuss their chemical composition: that was Rinman’s task. In 1779,
however, he analysed brown tourmalines from Zillerthal in Tyrol sent to him by
von Born, and compared them to tourmalines from Sri Lanka [2]. The problem was
that the stones were not soluble in acids, and thus he used his method of fusing the
powdered samples with alkali (Sect. 23.4). He concluded that the tourmaline of
Tyrol was composed of 42 parts clay, 40 parts silica, 12 parts lime and 6 parts iron,
while the stones from Sri Lanka were composed of 39 parts clay, 37 parts silica, 15
lime and 9 parts iron. As the composition of tourmalines varies, the accuracy of
© Springer Nature Switzerland AG 2020
A. Lennartson, Carl Wilhelm Scheele and Torbern Bergman, Perspectives on the
History of Chemistry, https://doi.org/10.1007/978-3-030-49194-9_25
343
Bergman’s Contributions
to Mineralogy
As the majority of Swedish chemists up to the mid-nineteenth century, Bergman
had a natural interest in mineralogy. In fact, due to the influence of the Board of
Mines, he had to develop such an interest. This interest resulted in several papers on
mineral analysis (Chap. 23) and two works on classification of minerals. To his
help, Bergman had his extensive mineral collection (Sect. 9.4), but he also made
several trips through Sweden during the summers to visit mines and other places of
mineralogical interest. He also received mineral samples from colleagues around
Europe. Since Bergman’s analytical methods were discussed in Chap. 23, this
chapter will focus on his analytical results and conclusions.
25.1 Semi-precious Stones and Gems
The October to December issue of the Transactions of 1777 featured a series of five
papers in a row on a mineral called Oculus mundi (world’s eye), now called
hydrophane and recognised as a rare variety of opal. The last of these papers,
Tilläggning om Oculus mundi [1] (addition on Oculus mundi), was written by
Bergman. Bergman’s addition to the discussion on this mineral was whether it was
properly classified as an opal or carnelian. Bergman also used hydrochloric acid
(Acidum salis) to extract aluminium (earth of alum) from Oculus mundi.
In his 1766 paper on the electrical properties of tourmalines (Sect. 5.2), Bergman
did not discuss their chemical composition: that was Rinman’s task. In 1779,
however, he analysed brown tourmalines from Zillerthal in Tyrol sent to him by
von Born, and compared them to tourmalines from Sri Lanka [2]. The problem was
that the stones were not soluble in acids, and thus he used his method of fusing the
powdered samples with alkali (Sect. 23.4). He concluded that the tourmaline of
Tyrol was composed of 42 parts clay, 40 parts silica, 12 parts lime and 6 parts iron,
while the stones from Sri Lanka were composed of 39 parts clay, 37 parts silica, 15
lime and 9 parts iron. As the composition of tourmalines varies, the accuracy of
© Springer Nature Switzerland AG 2020
A. Lennartson, Carl Wilhelm Scheele and Torbern Bergman, Perspectives on the
History of Chemistry, https://doi.org/10.1007/978-3-030-49194-9_25
343