Is green tree agate igneous metamorphic or sedimentary rock?

Green tree agate is not classified as an igneous, metamorphic, or sedimentary rock; rather, it is a type of chalcedony, which is a microcrystalline form of silica. It forms in volcanic environments, often as a result of the deposition of silica from hydrothermal fluids. While it has some characteristics associated with both igneous and sedimentary processes, it is primarily considered a mineral rather than a rock type.