Brewsterite
Mineral (Sr,Ba,Ca)Al2Si6O16·5H2O
Also called Brewsterite-Sr and Brewsterite-Ba
About it
Short prisms with one pearly face, the only common strontium zeolite; classic crystals come from Strontian, Scotland, the village that gave strontium its name.
- Type
- Mineral
- Group
- Silicate (tectosilicate), zeolite group
- Formula
- (Sr,Ba,Ca)Al2Si6O16·5H2O
- Hardness (Mohs)
- 5–5.5
- Specific gravity
- 2.4–2.5
- Streak
- white
- Lustre
- vitreous (glassy), pearly
- Crystal system
- Monoclinic
- Colours
- white, colourless, yellowish, grey
- Transparency
- transparent, translucent
- Cleavage and fracture
- perfect in one direction
Typical values: real specimens vary. For more, see mindat.org.