Hutberg diorite
The Hutberg diorite comprises an occurrence in the Czech Republic near Žulová (Friedeberg) in the Reichensteiner Mountains . The diorite is named after its place of discovery, the 476 m high Kaní hora (Hutberg) west of Žulová. The dioritic masses on the Hutberg enclosed in the Friedeberger granite are divided into the hornblende-rich Hutberg diorite, the quartz mica diorite and the granodiorite .
Rock description and mineral inventory
When Hutbergdiorit is a small deposits, which was very popular in the Sudeten granite industry because of its dark coloring. The main parts of the mix are quartz and plagioclase . Small proportions of potassium feldspar , hornblende and biotite (dark mica) are added. Accessory involved are sphene , abundant apatite and little zircon . The similarity of the Hutberg diorite with the Woitzdorfer diorite near Vojtíškov (Woitzdorf) near Malá Morava (Klein Mohrau) suggests that the diorite occurrence on the Hutberg has similarities with the occurrence of Woitzdorf and that the continuation of this dioritic occurrence lies in the Hutberg zone west of Žulová.
The granodiorite from Starost (Sorge), a place southwest of Žulová, is very close to the granite of the Reichenstein Mountains of the Steinberg type. It consists of quartz, andesine and oligoclase , microcline , biotite and hornblende. Its secondary components are titanite, apatite , magnetite and zircon.
Fine to medium-grained, dark gray rocks were incorporated under the quartz mica diorites , which contain more plagioclase than quartz and hardly any potassium feldspar. Quartz mica diorite occurs east in the Schlippengrund (Žlíbek) and near the Engel houses and near Starost (Sorge) on the Brandkoppe as well as on the church hill near Žulová and Černá Voda (Schwarzwasser).
Occurrence
The diorites included in the granite deposits, which were preferred natural stones because of their dark color , occur in the form of clods in the Friedeberger granite mass. These are small deposits that were depleted relatively quickly. In a quarry on the south side of the Hutberg of the Fridolin Franke company from Tomíkovice , which existed there until the end of the Second World War, a mica rock was found, which is a sign of a melting transition. The same applies to the granite quarry of the Kulka company near Sorge when a block of rock was found containing garnet, a semi-precious stone. Grenades are a sign of rock metamorphosis (transformation) under heat and pressure.
The quartz mica diorite and the Hutberg diorite produce spherical formations that represent special weathering forms of these rocks. These forms were quite often found near the surface in the quarries there.
See also
literature
- L. Finckh and G. Götzinger: Explanation of the geological map of the Reichensteiner Mountains, the Nesselkoppenkamm and the Neisse foreland, ed. v. of the Federal Geological Institute in Vienna, Österreichische Staatsdruckerei, Vienna 1931, p. 40ff.