perrierite
/ˈpɛrɪərʌɪt/Mineralogy
noun
A monoclinic silicate of lanthanides, titanium, iron, and other elements, (Ca,Ce,Th)4(Mg,Fe2+)2(Ti,Fe3+)3Si4O22, occurring as black or reddish brown prismatic crystals.
Origin
1950s; earliest use found in Chemical Abstracts. From Italian perrierite from the name of Carlo Perrier, Italian mineralogist + -ite.