Silicic Andesite Research Articles

Silver content of igneous rocks

The following averages of silver for various types of Japanese igneous rocks have been obtained (in p.p.m.): granites 0.0037, granodiorites 0.050, liparites 0.049, quartz diorites and diorites 0.053, silicic andesites and andesites 0.080, basalts 0.11, diabases 0.12, gabbros 0.11 and ultramafic rocks 0.060. The crustal abundance of silver is estimated to be 0.08 p.p.m.