Question

which type of rock do you think is most likely to contain fossil

Answer 1

Sedimentary rocks are by far the most likely to contain fossils. Examples and why:

- Shale/mudstone: fine-grained sediments settle in calm water (lakes, deep marine) and preserve delicate details — excellent for soft-bodied and small fossils.
- Limestone: forms from accumulation of shells and skeletal fragments (calcium carbonate) in shallow seas, so it commonly contains marine fossils.
- Sandstone: preserves larger, tougher remains and trace fossils (tracks, burrows) from beaches, rivers, and deserts.
- Coal: compressed plant material — preserves plant fossils and sometimes insects.

Why not the others:
- Igneous rocks form from molten rock, which destroys organic material, so fossils are very rare.
- Metamorphic rocks have been recrystallized by heat and pressure, which usually distorts or destroys fossils (though in some low-grade cases remnants can survive).

Good places to look: sedimentary strata in river deltas, lake beds, floodplains, and shallow marine deposits.