Formula: [Zn(CON2H4)6]SO4. May contain unknown amount of water. I don't have much information on this compound, except of a few mentions about its existence. It formed, when urea CON2H4 and Zinc sulfate ZnSO4 are dissolved in water in 6:1 molar ratio and then crystallized.
- Crystal system: my guess is orthorombic.
- Crystal shape: parallelepiped with facets.
- Stability on air: stable, but easily absorbs water.
Dissolve 6 molar parts or urea and 1 molar part of zinc sulfate in minimal amount of water, with only mild heating. Avoid strong heating, because it causes formation of insoluble white sediment.
Use regular evaporation method, but take measures to reduce evaporation, because solubility is very high and even slow evaporation can cause excessive growth. My samples were grown in almost closed contaiener.
Should be safe. However, in large amounts zinc can be toxic.