The only Mars rocks we have on earth are Martian meteorites.
That's a given.
And the most famous [infamous] martian rock/meteorite is of course ALH84001.
Now here is the challenge...

If fossils are usually found in sedimentary rock, is the martian meteorite ALH84001
by any stretch of the imagination [or geo-definition] a sedimentary-type rock?

If the martian meteorite ALH84001 is NOT a sedimentary rock, but a 'pure' igneous
type [olivine basalt, etc...], wouldn't that put a "final nail in the coffin" for the theory that those segmented wormlike structures in ALH84001 might be micro-fossils?

Jacob

"Extraordinary claims, require extraordinary evidence."
CARL SAGAN