One of the most interesting crystals: a double salt of sodium, potassium and ferrioxalate ion that have deep green color, highly symmetric shape and great stability upon exposure to air. Unfortunately, I was not able to prepare aluminium analog: Na and K alumooxalates just crystallized separtely.
- Potassium tris(oxalato) ferrate (III): pure K salt
- Sodium tris(oxalato) ferrate (III): pure Na salt
- Sodium tris(oxalato) aluminate: Al analog