The geochemistry of the Randesund banded gneisses is described. It is concluded that the banded gneisses are the result of three processes: 1) gneissification of a quartzite/arkose succession, 2) lit-par-lit injection of basic magma, 3) some of the resulting amphibolites were striped and in some cases banded by metamorphic differentiation as a result of shearing.