Markl specializes in crustal petrology and geochemistry and has studied the hydrothermal ore deposits of the Black Forest area .
Markl found the type specimen of marklite in the dumps of the Friedrich - Christian mine in the Black Forest Mountains in southwestern Germany .
Markl specializes in crustal petrology and geochemistry and has studied the hydrothermal ore deposits of the Black Forest Mountains   area .
Markl found the type specimen of marklite in the dumps of the Friedrich - Christian mine in the Black Forest Mountains in southwestern Germany .