There are ~22 brachipod fossils located on this single rock. They are all molds. The rock measures ~61 mm (2.4 in) long, ~42 mm (1.6 in) wide and ~21 mm (.85 in) thick. The fossil in photo #1 measures ~3.6 mm (.14 in) tall and ~5 mm (.20 in) wide. This fossil dates to the Devonian Period (416-359.2 million years ago). I believe the rock is sandstone.
Rocky bottom of man-made lake. Pymatuning Lake. Andover, Ohio, USA
The extreme close up pictures were taken with a Digital Blue QX5 USB microscope at 10x power.