Andesites

Andesites: rocks belonging to the Basalt-Andesite family, occurring either as lava dikes or within large volcanic complexes often associated with Basalts and Trachytes. Light in color—generally gray or brownish—they typically display a porphyritic texture with phenocrysts of Plagioclase (mainly Andesine), Biotite, Hornblende, and Pyroxenes. Quartz content usually does not exceed 5%.

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