“...This canyon was once the site of several claims, but the entire area is now located within the Mill Creek Wilderness. Collecting is no longer allowed and the claims are abandoned. Some of the claims that were located in the canyon are Bear Springs, Tamarack I & II, Lavish Lady, Smokey Blue, Little Smokey Blue, Two Dogs, Sleeping Beauty, Ma Quant, Fly Ridge and Yellow Jacket.
It has become nearly impossible to identify documented thundereggs from any of these claims, so they are now generally known as Desolation Canyon egg (look at “Tabor Hall Thundereggs”) . They are becoming more and more rare as no new specimens are being produced. The eggs pictured from here are typical of the locality, many contain white to bluish-grey agate with mossy inclusions and have a greyish to greenish phorphyritic matrix...”
extract of the article from Mark Ketsdever, Hillsboro, Oregon, 2007 :”Thunderegg Agates of the Ochoco Mountains, Oregon, USA”