granite is not a mineral. neither is diorite.
the differences between granite, granodiorite, monzonite, quartz diorite, diorite, nepheline syenite, gabbro and dunite are chemical - the relative composition of the minerals making up the rock. quartz, three types of feldspar, mica, honblende and amphibolite usually. so granite has a lot of quartz and sodic feldspar, then as you go across the spectrum the feldspar changes with ratio of sodic to calcic and then potassium feldspar, and as you move into granodiorite and diorite you tend to lose the quartz altogether, then gabbro has almost no feldspar but is mostly mica, hornblende, amphibolite and other mafic rocks, finally you get dunite which is 100% olivine like the Twin Sisters.
Chemically the light-coloured granites are equal to the light-coloured lavas like rhyolite and dacite that form volcanic ash... diorite and gabbro are equivalent to andesite and basalt... take Geol 100 to find out why.