Green Onyx Meanings, Zodiacs, Planets, Elements, Colors, Chakras, and more. Science & Origin of Green OnyxGreen Onyx is often mistaken for Emerald and Jade but differs in formation and structure. It is formed through the layering of Chalcedony and Quartz in a cryptocrystalline formation, whereas Emerald for example, is a Beryl formation. This stone has a hardness of 6.5-7, similarly to most other forms of Onyx. The color of Green Onyx is a rich, deep green and it is primarily found in…