Radiolarian microfossils in a polished piece of chert from the Marin Headlands, at the northern side of the Golden Gate. (Link to album in comments) [OS][3000×2000]

Radiolarian microfossils in a polished piece of chert from the Marin Headlands, at the northern side of the Golden Gate. (Link to album in comments) [OS][3000×2000]

4 days ago