Orbiculite
Avatar

Orbiculite

by Mario Wipki, GFZ Potsdam, Potsdam, Germany

Orbiculite from W-Australia - can be visited opposite of the holocaust memorial in Tiergarten. Maybe the oldest exposed rock in Berlin - older than 2 billion years. See also www.globalstone.de/ comes from near Mount Magnet in Western Australia. The orbicules occur in a granodiorite matrix. They consist of andesine, plagioclase, hornblende biotite arranged radially around a core of plagioclase or hornblende or less commonly mafic schist.

Avatar

Klaus Gessner 7 years, 8 months ago

Please follow this link for information on where this rock naturally occurs, including geological background; http://www.nationalrockgarden.org.au/rock-collection-2/rock-listing/show/11