Pseudofossils may be misleading, as some types of mineral deposits can mimic lifeforms by forming what appear to be highly detailed or organized structures.
For example, Eozoön is a complex laminated form of interlayered calcite and serpentine originally found in Precambrian metamorphosed limestones (marbles).
Similar structures were subsequently found in metamorphosed limestone blocks ejected during an eruption of Mount Vesuvius.
It was clear that high-temperature physical and chemical processes were responsible for the formation of Eozoön in the carbonate rock (O'Brien, 1970).
Chemical gardens can produce branching microtubuli of 2-10 μm in diameter and can resemble very closely the shapes of fossilized primitive fungi or microorganisms.