enigmatite
noun
enig·ma·tite
variants:
or less commonly aenigmatite \ ə̇ˈnigməˌtīt , ēˈ- , eˈ- \
plural -s
Definition of enigmatite
: an imperfectly known mineral formerly classed with the amphibole group that occurs in black triclinic crystals and is essentially a silicate of iron, titanium, and sodium (specific gravity 3.74–3.80)
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