El granito, también conocido como piedra berroqueña, es una roca ígnea plutónica constituida esencialmente por cuarzo, feldespato y mica. Mientras el término según los estándares de Unión Internacional de Ciencias Geológicas refiere una composición estricta, el término granito es a menudo usado dentro y fuera de la geología en un sentido más amplio incluyendo a rocas como tonalitas y sienitas de cuarzo. Para el uso amplio de granito, algunos científicos han adoptado el término granitoide. Los granitoides son las rocas más abundantes de la corteza continental superior. Los granitoides cubren el 4,5 % de la corteza terrestre y el 15 % de los continentes. Los granitoides se producen al solidificarse lentamente magma con alto contenido en sílice en profundidades a alta presión. Magma de composición granítica que sale a la superficie forma riolita, el equivalente volcánico del granito.

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Granite (pronunciation: /ˈɡrænᵻt/) is a common type of felsic intrusive igneous rock that is granular and phaneritic in texture. Granites can be predominantly white, pink, or gray in color, depending on their mineralogy. The word "granite" comes from the Latin granum, a grain, in reference to the coarse-grained structure of such a holocrystalline rock. By definition, granite is an igneous rock with at least 20% quartz and up to 65% alkali feldspar by volume. The term "granitic" means granite-like and is applied to granite and a group of intrusive igneous rocks with similar textures and slight variations in composition and origin. These rocks mainly consist of feldspar, quartz, mica, and amphibole minerals, which form an interlocking, somewhat equigranular matrix of feldspar and quartz with scattered darker biotite mica and amphibole (often hornblende) peppering the lighter color minerals. Occasionally some individual crystals (phenocrysts) are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic texture is known as a granite porphyry. Granitoid is a general, descriptive field term for lighter-colored, coarse-grained igneous rocks. Petrographic examination is required for identification of specific types of granitoids. Granite differs from granodiorite in that at least 35% of the feldspar in granite is alkali feldspar as opposed to plagioclase; it is the potassium feldspar that gives many granites a distinctive pink color. The extrusive igneous rock equivalent of granite is rhyolite. Granite is nearly always massive (lacking any internal structures), hard and tough, and therefore it has gained widespread use throughout human history, and more recently as a construction stone. The average density of granite is between 2.65 and 2.75 g/cm3 (165.4 - 171.7 lb/ft3), its compressive strength usually lies above 200 MPa, and its viscosity near STP is 3–6 • 1019 Pa·s. The melting temperature of dry granite at ambient pressure is 1215–1260 °C (2219–2300 °F); it is strongly reduced in the presence of water, down to 650 °C at a few kBar pressure. Granite has poor primary permeability, but strong secondary permeability.

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