âº The coasts of the continents surrounding the Atlantic ocean could, if the continents were moved closer, fit together like a jigsaw puzzle. Reconstruction of previous position continents created with TimeTrek. âº Living animals in widely separated lands are similar.
The rock limestone is mostly made up of one of two types of mineral â either calcite or aragonite. Both of these are different crystal arrangements of the same chemical compound â calcium carbonate (CaCO 3).
1 One of the largest areas of limestone [limestone: A sedimentary rock consisting mainly of calcium carbonate. 2  It is commonly used as a building stone. ] 3  in the UK is found in the Yorkshire Dales National Park, near Malham and Ingleton. 4  Limestone is a sedimentary rock made of calcium carbonate.