In geology|lang=en terms the difference between igneous and peraluminous

is that igneous is (geology) resulting from, or produced by, the action of great heat; with rocks, it could also mean formed from lava/magma; as, granite and basalt are igneous rocks while peraluminous is (geology) describing igneous rocks that have a higher molar proportion of aluminium to sodium, potassium and calcium.

As adjectives the difference between igneous and peraluminous

is that igneous is pertaining to, having the nature of fire; containing fire; resembling fire; as, an igneous appearance while peraluminous is (geology) describing igneous rocks that have a higher molar proportion of aluminium to sodium, potassium and calcium.