Granodiorite is a phaneritic, intrusive igneous rock similar to granite but containing more plagioclase feldspar than orthoclase. It is commonly found in large batholiths and is characterized by a salt-and-pepper appearance caused by the mixture of light-colored minerals and darker mafic components.

Hardness

6-7

Mohs

Luster

Vitreous

Transparency

Opaque

igneouscommon

Granodiorite

Hardness: 6-7
Luster: Vitreous
Transparency: Opaque

Is this granodiorite?

4-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch granodiorite with a known reference. Granodiorite sits at Mohs 6-7, softer than the next harder reference, harder than the previous one.
2
Read the luster
Hold the specimen under a strong light. Granodiorite typically shows a vitreous luster.
3
Match the color range
Compare against the expected color range: gray, white, black, speckled.
4
Look at form & habit
Typical habit: phaneritic granular.

Often confused with

Granodiorite vs. its common look-alikes, and how to tell them apart in the field.

Often found alongside granodiorite

Minerals reported to co-occur with granodiorite. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Mohs hardness: 6-7
Density: 2.65-2.75 g/cm³
Colors: Gray White Black Speckled
Luster: Vitreous
Transparency: Opaque
Crystal habit: Phaneritic Granular
Rarity: Common
Uses: Construction, Architecture, Decorative
Host rock: Plutonic Igneous
Typical price: $1-10 specimen

Where rockhounds find granodiorite

Classic worldwide localities

United States
Canada
Norway
Scotland
Australia

Field-hunting tip

Look in plutonic igneous country, the host setting where granodiorite typically forms. If you start seeing quartz, plagioclase, potassium feldspar in float, you are in the right ground. Field specimens usually show a phaneritic granular habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify granodiorite?+

Mohs hardness is 6-7. It typically shows a vitreous luster. Common colors include gray, white, black, speckled.

Where is granodiorite found?+

Notable localities include United States; Canada; Norway; Scotland; Australia.

How much is granodiorite worth?+

Typical asking prices fall in the range of $1-10 specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like granodiorite?+

Granodiorite is most often confused with Granite, Diorite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with granodiorite?+

Granodiorite commonly co-occurs with Quartz, Plagioclase, Potassium Feldspar, Biotite, Hornblende. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does granodiorite form in?+

Granodiorite typically forms in plutonic igneous. Working float back to the host body is the standard way to chase a fresh occurrence.

What is granodiorite used for?+

Granodiorite is used in construction, architecture, decorative.

Find granodiorite on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.