Thenardite
Mineral Na2SO4
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
Salty crusts and dipyramids from dry lake beds such as Searles Lake in California. Soluble in water and turns powdery as it takes up moisture; often forms as mirabilite dries out.
- Type
- Mineral
- Group
- Sulfate, anhydrous
- Formula
- Na2SO4
- Hardness (Mohs)
- 2.5–3
- Specific gravity
- 2.66–2.68
- Streak
- white
- Lustre
- vitreous (glassy), resinous
- Crystal system
- Orthorhombic
- Colours
- colourless, white, grey, yellowish, brownish
- Transparency
- transparent, translucent
- Cleavage and fracture
- perfect in one direction
Typical values: real specimens vary. For more, see mindat.org.