vivianite
[ viv-ee-uh-nahyt ]
/ ˈvɪv i əˌnaɪt /
noun
a secondary mineral, hydrous ferrous phosphate, Fe3(PO4)2⋅8H2O, occurring in the form of pale blue crystals or powder.
Origin of vivianite
1815–25; named after J. G.
Vivian, 19th-century English mineralogist, who found it; see
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