Specimen data for Stilbite

Tom Mortimer catalog number: 1037

Identification method: Visual.

Notes: The stilbite crystals on this specimen were collected from a seam close to the surface and have experienced some weathering. These are, however, the largest stilbite crystals, (particularly as a cluster group), that I have seen from New Hampshire.
There two species "flavors" of stilbite: Stilbite-Na and Stilbite-Ca. The Na, Ca content ratio of this specimen has not been determined. There is moderate variation in the chemical formulas for stilbite. Recently on mindat we have:
Stilbite-Ca: NaCa₄(Si₂₇Al₉)O₇₂·28H₂O
Stilbite-Na: Na₉(Si₂₇Al₉)O₇₂·28H₂O