Word Study
andesite
CIDE DICTIONARY
andesite, n.
An eruptive rock allied to trachyte, consisting essentially of a triclinic feldspar, with pyroxene, hornblende, or hypersthene. [1913 Webster]
OXFORD DICTIONARY
andesite, n. a fine-grained brown or greyish intermediate volcanic rock.
Etymology
Andes mountain chain in S. America + -ITE(1)
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