- Monteregianite-(Y) (type locality) with Pectolite on Albite
- Miniature, 4.5 x 3.0 x 2.0 cm
- Monteregian intrusive, Poudrette quarry, Mont Saint-Hilaire, La Vallee-du-Richelieu RCM, Monteregie, Quebec, Canada
- Ex. Paulo Matioli
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.