Kieserite
Mineral MgSO4·H2O
Take care.
- Damaged by water: Keep it dry: don't wash it, and keep it out of damp places.
- Breaks down in damp air: Keep it dry and in steady humidity; some crumble or rot as they take on moisture.
About it
A granular white mineral of potash deposits that slowly takes up water and turns to epsomite in damp air. Mined in the Stassfurt district of Germany for fertilizer; rarely seen as crystals.
- Type
- Mineral
- Group
- Sulfate, kieserite group
- Formula
- MgSO4·H2O
- Hardness (Mohs)
- 3.5
- Specific gravity
- 2.55–2.6
- Streak
- white
- Lustre
- vitreous (glassy)
- Crystal system
- Monoclinic
- Colours
- colourless, white, greyish, yellowish
- Transparency
- transparent, translucent
- Cleavage and fracture
- perfect in two directions
Typical values: real specimens vary. For more, see mindat.org.