plural -s
: a brownish black mineral (Y,Er,Ce,Fe,)(Nb,Ta,Ti)O4 consisting essentially of an oxide of yttrium, erbium, niobium, and tantalum with other metals often including uranium and isomorphous with formanite (hardness 5.5–6)

Word History


Robert Ferguson †1865 Scottish physician + English -ite

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Dictionary Entries Near fergusonite

Cite this Entry

“Fergusonite.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fergusonite. Accessed 2 Oct. 2023.

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