Phillipsite
Mineral (K,Na,Ca)1-2(Si,Al)8O16·6H2O
Also called Phillipsite-K, Phillipsite-Ca, and Phillipsite-Na
About it
Small cross-shaped twins and radiating balls in basalt cavities; common but rarely large. Germany's Eifel, Sicily, and the deep Pacific sea floor, where it forms in sediment.
- Type
- Mineral
- Group
- Silicate (tectosilicate), zeolite group
- Formula
- (K,Na,Ca)1-2(Si,Al)8O16·6H2O
- Hardness (Mohs)
- 4–4.5
- Specific gravity
- 2.15–2.2
- Streak
- white
- Lustre
- vitreous (glassy)
- Crystal system
- Monoclinic
- Colours
- colourless, white, pink, yellowish
- Transparency
- transparent, translucent
- Cleavage and fracture
- distinct in one direction
Typical values: real specimens vary. For more, see mindat.org.