Google Pixel5 cell phone and metric ruler for measurement.
I took a day off to travel back in time to the Green River Formation of the Eocene era. The location was a pay to dig fossil quarry. This fossil fish pictured is commonly called a Diplo. Actual name is" Diplomystus dentatus (Cope, 1877) is well known from lower Eocene deposits from the Green River Formation in Wyoming." - Wiki
It was a fun and rewarding excursion back in time. I split about 1000 pounds of rock in 7 hours and was able to take home all the fossils I found...about 30 or so decent one. There was probably a 50 percent damaged fossil vs a complete one due to the fragile nature of the matrix they were embedded in. I hope that the other fish prep out as well as this very first one. After the split is was 30 percent covered it matrix which I picked out with a needle probe and medium stiff bristle brush.