YOWAH Nut, from Yowha Paroo area, Queensland. 
Yowah Nut is considered a "Dreamtime stone" with a connection to Mother Earth. 
Cut from a single nut have a unique pattern nut-like shape, formed by a core of opal surrounded by a shell of ironstone. The Yowah Nut is a type of boulder opal, characterized by its unique formation and with veins of colors.