- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography and Index of Geology Exclusive of North America, Geological Society of America, Boulder, CO, United States
Various examples of granites whose compositions differ in essential, as well as minor and accessory, constituents are cited. An even greater variation is shown in associated ore deposits. It is concluded that these variations are more easily explained by magmatic differentiation than by other theories.