Changes

[[Image:Four of the Seven Sisters.jpg|thumb|200px|Four of the "Seven Sisters" along the [[Sussex]] coast, [[England]]]]

[[Image:Four of the Seven Sisters.jpg|thumb|200px|Four of the "Seven Sisters" along the [[Sussex]] coast, [[England]]]]

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

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

Nowadays, chalk has been replaced by other substances.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Nowadays, chalk has been replaced by other substances.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:Sedimentary rocks]]

[[Category:Sedimentary Rocks]]