Changes

Chalk is a white, Sedimentary rock, composed of calcite.  

'''Chalk''' is a white, sedimentary rock, composed of calcium carbonate. On of it's most dramatic outcrops is along the south coast of [[England]] where it forms the "white cliffs of [[Dover]]".

Nowadays, chalk has been replaced by other substances. For example, the "chalk" that is used in blackboard writing or in sidewalk chalk is actually gypsum.

Nowadays, chalk has been replaced by other substances. For example, the "chalk" that is used in blackboard writing or in sidewalk chalk is actually gypsum.

[[Category:Geology]]

[[Category:Sedimentary rocks]]