A true museum-quality display specimen with multiple critters: The stunning fossil shell in the middle is 9 cm long and has an intense iridescent opalization that produces a beautiful play of colors both on the surface and internally. Normally, the opalization is a surface effect but this piece is translucent throughout when backlit. Note that it does have one clean repair near the tip. The shells fit into the matrix, which came from the same horizon as the fossil shell, and in which they were re-emplaced for display purposes after removal to clean and polish their surfaces (as is normal for this material). These very rare opal-replaced fossil shells were formed 135 million years ago and are unique to Australia. The supply at this famous locality, where the town of Coober Pedy is actually dug into the formation, has been exhausted as mining here is no longer profitable or commercially successful on any scale. These gem-quality specimens hold considerable value simply as opal for carving purposes and represent some of the cream of the crop assembled by a local collector during the 1960s-1980s mostly. Specimens of this quality are simply unavailable on the market. We are honored to present this private collection for the first time.