The most eastern occurrence of the Spitz granodiorite gneiss can be found on the Steinborz. The rock is similar to the Gföhl gneiss near Dürnstein and Loiben, a so-called orthogneiss, which developed from a granitic rock through metamorphosis. Dark, base-rich amphibolite is also found, a constant companion to the Spitz granodiorite gneiss. In the Steinborz vineyard, both rocks are strongly weathered and have a deep crumbly structure. Cracks and joints are filled with precipitated carbonate, a gift from the former loess cover that still exists in other areas. The high degree of weathering of the rocks allows the vines to exploit a large rooting zone.