The commonest hornblende is dark brown barkevicite.
The rocks are liparites, dacites, hornblende and pyroxene andesites.
Hornblende schists also occur and a compact felspathic rock in the Suris defile.
Thus, for instance, near Nikko in the upper valley of the Daiya-gawa, and in several other places in the neighboring mountains, a granite-porphyry appears with large, pale, flesh-colored crystals of orthoclase, dull triclinic feispar, quartz and hornblende.
In the Piedmont Plateau and Appalachian Mountains Regions the surface soil is generally sandy, but in considerable areas the subsoil is a red clay derived largely from the decomposition of hornblende.