Containing or producing garnets; said of rocks or soil that yields garnets.
From garnet + -iferous (Latin -ifer 'bearing, producing'). A geological/mineralogical term using the productive Latin suffix.
Garnetiferous is pure scientific jargon—geologists coined it for rocks that reliably contain garnets, and it's so specialized that most English speakers have never encountered it, but it perfectly demonstrates how science builds vocabulary.
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