The work on this dissertation was carried out by assignment of Styromag Styromagnesit Steirische Magnesitindustrie GmbH (short: Styromag), St. Katharein/Laming. The task was to plan the extension of the existing open pit mine on magnesite in Wald am Schoberpaß. All documents related to the mine that could be found in Styromag as well as relevant literature were studied. The data consisted of communications, mine plans, other maps, bore hole data including reports and academic literature. Findings, which were considered to be important to this work can be found in the Appendix. Surprisingly it was found that not all bore hole data got digitalised previously; the missing data was added to the existing data sets and through this the model of the mineral deposit could be corrected. In 2010 and 2011 the mining area itself and the surrounding area got visited intensively to verify existing data and to get new information for the planning of the mining layout. The former underground mines on levels 839 and 883 were entered as well. These old galleries are of special importance to further work as they might limit the size of the future quarry. Magnesite from Wald is needed by Styromag processing plant in St. Katharein; a good proportion of the delivered material originates from two old dumps, which are within the mining area of the Wald deposit. At the moment the dump in the SE called “Schneeberger” is being worked on; for future use the dump in the NW called “Persch” has to be examined. Nevertheless, the major part of the magnesite from Wald originates from the open pit mine Through the software Surpac 6.1.3 (by Gemcom) two alternatives for the extension of the mine were planned. First of all the more than 50 m high wall in the open pit mine has to be reduced to heights less than 15 m to ensure safe working conditions. Alternative #1 plans the extension of the current quarry to higher depths and to the NW. Right now the lowest level 3 in the mine is at an elevation of 866 m; this level has to be expanded to all sides. To achieve this the divider to the valley has to be narrowed and cut through in its NW part. At an elevation of 855 m the new level 2 can be started then. Through core drilling it has to be checked whether an expansion to the NW is feasible as the surface is covered by dump Persch with unknown thickness. Geophysical examination of dump Persch had been planned but was never carried out in the end. Alternative #2 is based on the extension of the quarry above 895 m in the SE part of the deposit. The core drills in the past were all taken below this elevation; due to this the deposit boundaries in this part are only estimated through outcrops and data from underground mining below 890 m. To be able to carry out this alternative, intensive core drilling has to be undertaken beforehand. Beside the magnesite the neighbouring rock has to be examined; its type and strength is determining the layout of the open pit mine and the amount of overburden in alternative #2. For the immediate constant supply of the Styromag processing plant with magnesite, alternative #1 has to be favoured as it works mostly within the known boundaries of the deposit; alternative #2 needs extensive prospecting and long term preparation. Due to the higher amount of overburden with alternative #2 the per ton costs with this alternative are naturally higher.