Helvines associated with contact aureoles of the Oslo Region are rich in Mn, moderately rich in Fe, and rather poor in Zn; mean for 5 localities: 60% Mn-helvine, 30% Fe-helvine, 10% Zn-helvine. Those from nepheline syenitic pegmatite are essentially Zn-helvines. Helvine from a granite pegmatite in Northern Norway is a nearly pure Mn-helvine. Some of the results are discussed.
Contributions to the mineralogy of Norway. No. 18. Classification of some Norwegian members of the Helvine Group.