The geological formation of carboniferous limestone rock is illustrated. Fossil formation is mentioned but not shown.

An animation shows the build up of layers of calcite (from marine organisms) combined with silt and sand which together form a grey, hard rock called limestone.

First broadcast:
17 February 2001

Compare the formation of limestone with that of other sedimentary rocks. Students could draw step-by-step diagrams of the formation of different rock types.