In April 1879, three researchers described independently the same hydrous calcium copper sulphate from Špania Dolina within a week (!). Benő Winkler presented the mineral as úrvölgyite (after the Hungarian name of the locality) at a proceeding of the Selmecbánya (now Banská Štiavnica) branch of the Hungarian Geological Society on 16 April 1879, József Szabó described it the same name at a meeting of the section III of the Hungarian Academy of Sciences on 21 April 1879, and Aristides Brezina described it as herrengrundite (after the German name of Špania Dolina) in a short printed article dated 22 April 1879. Internationally, the latter name has spread. Unfortunately, none of the mineral names are valid today, as Heinrich Hermann Meixner showed in 1940 that this mineral is identical to the devilline described by Félix Pisani from Cornwall, England in 1864, so for priority reasons, this is the official name today.
In the picture: Devilline, Špania Dolina (Slovakia). Image width: 2 cm. Photo by László Tóth.