The color green (wadj) was the color of vegetation and new life. To do "green things" was slang for beneficial, life-producing behavior. As mentioned above, Osiris was often portrayed with green skin and was also referred to as "the Great Green". Green malachite was a symbol of joy and the land of the blessed dead was described as the "field of malachite." In Chapter 77 of the Book of the Dead, it is said that the deceased will become a falcon "whose wings are of green stone". Highly impractical of course, it is obvious that the color of new life and re-birth is what is important. The Eye of Horus amulet was commonly made of green stone as well.
The pigment green could be produced from a paste manufactured by mixing oxides of copper and iron with silica and calcium. It could also be derived from malachite, a natural copper ore.