Yes. If you cannot, see the first micrograph below:
Don’t use chemistry or location to identify fossils.
Many people like to use chemical composition of material to identify fossils (note 1). However, Wikipedia article says clearly:
“This process (in fossilization) can occur in very small spaces, such as within the cell wall of a plant cell.” (note 2)
“In some cases the original remains of the organism have been completely dissolved or otherwise destroyed.” (note 3)
So, many fossil cells can be just casts. That means those fossil cells are just like rock minerals except for their shape/size and their origins in biology. Just one recent example: Edit [Moderator]: Link removed
Many anatomists need to study the location (context) of cells in order to identify fossil cells. They are not used to things that are long dead and distorted out of context as shown in this micrograph:
Edit [Moderator]: Link removed
So, they may not be sure about fossil cell identification.
Note 1: a recent example
Note 2: Wikipedia article paragraph
Note 3: Wikipedia article paragraph