Sodium Zinc Sulfate

Artificial changoite, formula: Na₂Zn(SO₄)₂·4H₂O Double sulfate of zinc and sodium. Natural variety of this compound is known as mineral сhangoite.

Properties

• Crystal system: monoclinic.
• Crystal shape: tabular, with striations on sides
• Stability on air: stable

Preparation

Dissolve equimolar amounts of sodium sulfate (usually Na₂SO₄·10H₂O) and zinc sulfate (ZnSO₄·7H₂O) in water, then crystallize. The compound is very soluble, so water should barely cover solid salts.

Growing

I used regular slow evaporation method. This copound has good solubility (my very rough guess - between 50 and 100 g per 100ml), so evaporation should not be too fast.

Safety

Mostly safe, though in significant amounts zinc can be toxic.

More photos

References

• My blog
• Mindat on Changoite