Sedimentary rocks close sedimentary rockSedimentary rocks ... which originates from clay. Slate is dark grey/green in colour and can be split into thin layers for use as roofing material.

The only exception to the rule is Country Tyrone which has a bit of everything - clay, basalt ... become compacted to form a new type of rock called sedimentary rock. Think of it as recycled ...

Shale is a sedimentary rock made up of tiny grains of silica, clay and other minerals. Many types of rock have few physical ...