igneous
Granite / Diorite (Granodiorite)
Granodiorite / Quartz Diorite
Phaneritic (coarse-grained) intrusive texture. Color is mottled black and white ('salt-and-pepper'). Mohs hardness around 6-7. Luster is vitreous to dull. Composed primarily of plagioclase feldspar, quartz, biotite mica, and amphibole (hornblende).
Identified More igneous →
Explore Granite / Diorite (Granodiorite) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Phaneritic (coarse-grained) intrusive texture. Color is mottled black and white ('salt-and-pepper'). Mohs hardness around 6-7. Luster is vitreous to dull. Composed primarily of plagioclase feldspar, quartz, biotite mica, and amphibole (hornblende).
Formation & geological history
Formed from the slow cooling and crystallization of magma deep below Earth's surface within plutons and batholiths in continental crustal environments.
Uses & applications
Extensively used as a dimension stone, building material, kitchen countertops, monuments, paving blocks, and crushed stone for road aggregate.
Geological facts
Granodiorite is the intermediate rock between granite and diorite. Famous structures made of granodiorite include the Rosetta Stone and Mount Rushmore.
Field identification & locations
Identified by its interlocking coarse grains of light-colored feldspar/quartz and dark-colored ferromagnesian minerals without significant foliation. Widespread in mountain ranges, continental shields, and batholith complexes worldwide.
