Granodiorite

Granodiorite is a coarse-grained intrusive igneous rock rich in quartz and plagioclase, with more plagioclase than alkali feldspar. Its mineral proportions distinguish it from granite and tonalite.

Quartz: Quartz is a hard crystalline mineral composed of silicon dioxide, common in many igneous rocks. Its abundance is one of the defining features of granodiorite.
Intrusive rock: Intrusive rock forms when magma crystallizes beneath Earth’s surface. Granodiorite’s crystals grow as its magma cools underground.
Granite: Granite is a coarse-grained intrusive rock containing abundant quartz and feldspar, with alkali feldspar at least as abundant as plagioclase. Granite has more alkali feldspar relative to plagioclase than granodiorite.
Dimension stone: Dimension stone is natural rock quarried and cut to specified sizes for construction or decoration. Granodiorite can be quarried for durable slabs, blocks, and architectural stone.
Plagioclase: Plagioclase is a series of feldspar minerals ranging from sodium-rich albite to calcium-rich anorthite. It exceeds alkali feldspar in granodiorite and helps set its classification.
Magma: Magma is molten or partially molten rock beneath Earth’s surface, containing crystals and dissolved gases. Granodiorite crystallizes from magma with an appropriate silica and feldspar composition.
Tonalite: Tonalite is a coarse-grained intrusive rock rich in quartz and plagioclase, with little alkali feldspar. Tonalite has less alkali feldspar than granodiorite under standard modal classification.
Aggregate (geology): Aggregate is granular construction material such as crushed stone, gravel, or sand. Crushed granodiorite supplies aggregate for roads and concrete.
Alkali feldspar: Alkali feldspar is a group of potassium- and sodium-rich feldspar minerals, including orthoclase and microcline. Its proportion relative to plagioclase separates granodiorite from granite.
Fractional crystallization: Fractional crystallization is the separation of early-formed crystals from magma as it cools. It can alter magma composition toward the felsic compositions that form granodiorite.

Linked from 5 pages