Gary Green Bog Agate / Larsonite / McDermitt Bog Agate
Gary Green Jasper, also known as Larsonite or McDermitt Bog Agate and more recently Caldera Jasper and now Freedom Jasper, is a beautiful greenish layered and swirled material formed when silica-rich fluids filtered through rhyolite ash, precipitating jasper along with other elements that give it the unique colors. Originally, the tight layering of the rhyolite was thought to be petrified wood from a swamp full of trees, cattails, algae and other material was buried by a volcanic event about 12 million years ago. However, recent research indicates that no plant material is present. The rhyolite is associated with the McDermitt Caldera, a large volcano that violently erupted numerous times throughout its history, depositing thick layers of ash. The McDermitt Volcano is along the same line as the Yellowstone Caldera. Over millions of years North America has been moving west, and the hot spot underneath the continent has stayed stationary. As a result, the appearance of the volcano on the surface has moved west from California to now Wyoming.