low-grade

[ loh-greyd ]
/ ˈloʊˈgreɪd /

adjective

of an inferior quality, worth, value, etc.: The mine yields low-grade silver ore.

Origin of low-grade

First recorded in 1875–80; low1 + grade
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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