It is white or grey flake,particle or massive crystallization Type I:15 mm max flakys TypeII:12 mm max flakys
Detailed
It is white or grey flake,particle or massive crystallization.Apt to cake after moisture absorption when laid in air for a long time.A little green because of Fe2+ ,yellow when Fe2+ is oxided to Fe3+.Soluble in water easily,and water solution is acid