The lateral secretion origin of Fe and Zn ores, resulting from metasomatism and/or recrystallization of amphibolites and biotite-rich gneisses in New Jersey and New York, USA

During K- and Si-metasomatism of deformed, relatively-mafic parent rocks to form more felsic, granitic rocks containing myrmekite, Ca, Mg, and Fe must leave the system as the modified rock is enriched in K, Na, and/or Si. When this kind of metasomatism occurs, the subtraction of Ca, Mg, and Fe would also be accompanied by losses of other metals present in the ferromagnesian silicates that were replaced by quartz. Such metallic elements could be deposited in adjacent rocks in ore concentrations by a process of lateral secretion. Such a process may explain the origin of Zn concentrations in New York