Until the end of the 18th century, mineralogists almost exclusively
used the laboratory techniques of chemistry. This drastically
changed with the invention of the goniometer and the polarizing
microscope. The development of mineralogy and crystallography
largely depended on these two instruments. Their importance
diminished with the discovery of the diffraction of x-rays by
crystals (1912) and its practical application in both sciences
during the course of the 20th century.
The invention of the goniometer (illustrated
in a separate collection of the Virtual Museum) initiated a
period of major advancements in the mineralogical and crystallographic
The polarizing microscope
instruments such as polariscopes, dichroscopes, refractometers, and the axial angle apparatus, appeared during the 19th century. They not only
helped the understanding of crystal optics, but also led to
the advancement of quantitative mineralogy. In the early 19th century (Haüy, 1817) instrumental
optical techniques were also introduced in testing cut and polished
Still today the
polarizing microscope remains a useful instrument in mineralogical
laboratories. The early, often elegantly constructed polarizing
microscopes and their innumerable and ingenious auxiliary accessories
are highly sought after by collectors.
Past the middle of the 19th century the apparition of the Bunsen
burner and the improved technology to produce better quality
glass for prisms opened the way to spectroscopy.
This technique which was then known as spectrochemical analysis
superseded the blowpipe method for the identification of elements.
A number of varieties of spectroscopes, from small pocket devices
to very sophisticated and precise instruments, were made by
a large number of instrument makers throughout Europe. Spectroscopy
underwent a fundamental change with the invention of the mass
spectrograph by Thomson and Aston in 1919.
- Burchard, U. and Medenbach, O. (2009) The Refractometer, The Mineralogicam Record, 40,
- Haüy, (1817) Traité des Caractères Physiques des Pierres
Précieuses, pour servir à leur détermination lorsqu'elles
ont été taillées, Paris
- James, F. (2003) Spectroscopy, in The Oxford Companion
to the History of Modern Science, Oxford
- Kile, D.E. (2003) The petrographic microscope, The Mineralogical
Record, Special publication no 1, Tucson