Limestone and Shale

Limestone noun - A sedimentary rock consisting mainly of calcium that was deposited by the remains of marine animals.

Shale and limestone are semantically related. in rock formed from sediment topic. In some cases you can use "Shale" instead a noun "Limestone".

Shale noun - A sedimentary rock formed by the deposition of successive layers of clay.

Limestone and shale are semantically related. You can use "Limestone" instead a noun "Shale".