science · 10 May 1860 · 164 years ago
In 1860, the discovery of two new elements, caesium and rubidium, was announced by German chemists, Robert Bunsen and Gustav Robert Kirchhoff to the Berlin Academy of Scientists. Their salts were found in tiny amounts in the mineral waters of Dürkheim. They were detected by spectral analysis. Caesium was first noticed by its characteristic sky blue spectral lines, for which colour is was named (from Latin caesius). Likewise rubidium was characterized by deep red lines (named after L. rubidus). They are alkali metals, and have similar chemical properties to potassium.
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