The Upper Bed, located in Malheur County, Oregon, is a productive thunderegg site known for its vibrant agate centers and strong internal contrast. Thundereggs from this bed often feature rich reds, oranges, and purples, with moss or plume inclusions that create dramatic visual depth when cut. The rhyolite matrix is typically reddish and coarse, with nodules ranging from medium to large and generally well-formed. Upper Bed material is favored by lapidary artists for its reliable cutting quality and bold color palette, making it a standout among the many thunderegg-producing beds in the region.
Rocks of the Cascades – Thundereggs, Tools & Tradition