Stilbite
Mineral NaCa4(Si27Al9)O72·28H2O
Also called Stilbite-Ca, Stilbite-Na, and Desmine
About it
Sheaf- or bow-tie-shaped bundles of crystals with a pearly face, white to salmon pink; abundant in the basalts of India and Nova Scotia's Bay of Fundy, whose provincial mineral it is.
- Type
- Mineral
- Group
- Silicate (tectosilicate), zeolite group
- Formula
- NaCa4(Si27Al9)O72·28H2O
- Hardness (Mohs)
- 3.5–4
- Specific gravity
- 2.1–2.2
- Streak
- white
- Lustre
- vitreous (glassy), pearly
- Crystal system
- Monoclinic
- Colours
- white, cream, peach, pink, orange, brown
- Transparency
- transparent, translucent
- Cleavage and fracture
- perfect in one direction
Typical values: real specimens vary. For more, see mindat.org.