They are mostly true felspar basalts, but a few contain nepheline in addition to the felspar.
1); in others it is scarce and the rocks resemble trachytes containing a little nepheline (trachytoid phonolites).
Leucite and nepheline lavas are here abundant.
Nepheline basalts and liparites occur at Dombe Grande.
Eruptive rocks of Palaeozoic age are met with in the Kola peninsula (nepheline-syenites) and at Kuusamo (syenite).
The Cainozoic series of New South Wales contains many interesting volcanic rocks, including leucite-basalts, nepheline-basalts and sodalite-basalts.
Kaolin and muscovite are formed principally after felspar (and the felspars are the commonest minerals of all crystalline rocks); also from nepheline, leucite, scapolite and a variety of other rock-forming minerals.