Paris green (copper(II) acetate triarsenite or copper(II) acetoarsenite) is an inorganic compound. It is a highly toxic emerald-green crystalline powder that has been used as a rodenticide and insecticide, and also as a pigment, despite its toxicity. It is also used as a blue colorant for fireworks. The color of Paris green is said to range from a pale blue green when very finely ground, to a deeper green when coarsely ground.