A rare specimen from the type and only locality! White, flattened prismatic crystals of monteregianite-(Y) to 1.5 mm with colorless, prismatic pectolite (to 1.5 mm) on white albite. Monteregianite-(Y) is a rare sodium potassium yttrium calcium silicate hydrate found in miarolitic cavities and other occurrences in nepheline syenite intrusive at Mont Sainte-Hilaire in the Monteregian Hills of Quebec. Ex. Paulo Matioli collection.