The story
Named for type locality Mount Royal in Montreal, where the mineral was discovered, + -ite.
Etymology from Wiktionary, CC BY-SA 4.0.
montroyalite
Today it means: a whitish brittle translucent fibrous crystalline mineral with the empirical chemical formula Sr₄Al₈(CO₃)₃(OH)₁₃F₁₂•10.5(H₂O) Full definition →