Juglans clarnensis Scott
Eocene
Clarno Formation
Clarno’s Ferry
Oregon, USA.

Juglans clarnensis was an extinct species of walnut tree known from fossil deposits of the Eocene Epoch, particularly the Clarno Formation of Oregon. The species name clarnensis refers to this famous fossil-bearing region, which preserves lush subtropical ecosystems dating to roughly 44–40 million years ago. You’re looking at the actual fruit (the “meat” you eat when you crack open a walnut), preserved in agate.
17mm nut in 51mm matrix