Public domain photos

The image shows a small piece of rock with a black and yellow pattern on it, sitting on a white surface with a board with numbers written on it. At the bottom of the image, there is a watermark indicating that it is a fossil of a zebra mussel from the Cretaceous period.

The image shows a small piece of rock with a black and yellow pattern on it, sitting on a white surface with a board with numbers written on it. At the bottom of the image, there is a watermark indicating that it is a fossil of a zebra mussel from the Cretaceous period.Open in library