Griceite was first described from Mont Saint-Hilaire and is the first known natural occurrence of lithium fluoride. It is a late stage mineral occasionally lining and filling cavities in sodalite xenoliths.
Color varies from pure white to pale yellow to very pale greenish yellow.
Luster is porcelaneous to waxy to dull. Diaphaneity is transparent when fresh, rapidly becoming translucent to opaque. Crystal Habits include compact powdery to bortyroidal masses lining and filling cavities, masses of tiny cubes stacked to form prismatic aggregates 2-3mm long, and as tiny plates and blobs embedded in villiaumite. Fracture is uneven to conchoidal. Streak is white.