Ummmm--could be----
“Cornelians” were not all dug—many were though.
If it is a “Cornelian” it would backlight as semi-transparent.
Straight on, these type look opaque—even with direct lighting.
The yellow streak does not throw me off here because the white in a “Cornelian” will show in this color because it is buried.
White should show though in my humble experience with this type of Akro.
Nice assessment Steph!
Marble—On!!