'''Cement''' is a substance that can bind other materials together. It is made by heating limestone with clay and plaster ([[calcium]], [[silicon]], [[iron]], and [[aluminum]]) and in some cases Pozzolanic ash.
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'''Cement''' is a substance that can bind other materials together. It is made by heating [[limestone]] with [[clay]] and [[plaster]] ([[calcium]], [[silicon]], [[iron]], and [[aluminum]]) and in some cases Pozzolanic ashes.