These are from the Blue bed, a bed just over the Stateborderfence at the Oregon-side as I heard.
Also Greenskins come from the Blue bed, a name for a spot.
Some of the eggs are membrane wreckage eggs. When the first mineralization has come of a cavities wall and has been ‘caught’ by agate, the term membrane wreckage is used.
Membrane wreckage is not very rare in amygdaloid agates found in some area’s, for example the Idar-Oberstein region in Germany.
Lithophysae are showing this phenomena very rarely. One of the few known localities with MW-thundereggs is the Blue bed, in which these stunning eggs occasionally are found.