Glauberite
Mineral Na2Ca(SO4)2
Take care.
- Damaged by water: Keep it dry: don't wash it, and keep it out of damp places.
About it
Steep, sharp-edged tablets in salt beds that slowly break down in water. Often met as casts and pseudomorphs, where quartz, calcite, or prehnite filled the space of crystals that dissolved away.
- Type
- Mineral
- Group
- Sulfate, anhydrous
- Formula
- Na2Ca(SO4)2
- Hardness (Mohs)
- 2.5–3
- Specific gravity
- 2.75–2.85
- Streak
- white
- Lustre
- vitreous (glassy), waxy, pearly
- Crystal system
- Monoclinic
- Colours
- colourless, grey, yellowish, pale brown
- Transparency
- transparent, translucent
- Cleavage and fracture
- perfect basal; conchoidal fracture
Typical values: real specimens vary. For more, see mindat.org.