Why do not all rock types contain fossils? Excessive heat and pressure can destroy fossils.
Fossils can only be created in certain places around the world.
Fossils cannot be created near volcanoes.
Fossils are too large to be found in igneous and metamorphic rocks.

Igneous rocks form from molten rock, and rarely have fossils in them. Metamorphic rocks have been put under great pressure, heated, squashed or stretched, and fossils do not usually survive these extreme conditions. Generally it is only sedimentary rocks that contain fossils.

Explanation:

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