hieratite
noun
hi·er·a·tite
ˈhīərəˌtīt
plural -s
: a mineral K2SiF6 consisting of potassium fluosilicate found as grayish concretions in the fumaroles of Vulcano
Word History
Etymology
Italian, from Hiera (Vulcano), one of the Lipari islands, Italy + Italian -ite