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gabbro vs. basalt

[gab-roh] / ˈgæb roʊ /

noun

Petrology.

plural

gabbros
  1. a dark granular igneous rock composed essentially of labradorite and augite.

[buh-sawlt, bas-awlt, bey-sawlt] / bəˈsɔlt, ˈbæs ɔlt, ˈbeɪ sɔlt /

noun

  1. the dark, dense igneous rock of a lava flow or minor intrusion, composed essentially of labradorite and pyroxene and often displaying a columnar structure.