What is Carnelian?
[[File:Carnelian intaglio Prolemaic queen CdM Paris.jpg|thumb|250px|Intaglio (engraved) showing a Ptolemaic queen, 1st century BC. ]] '''Carnelian''' (also spelled cornelian) is a brownish-red mineral commonly used as a semi-precious gemstone.<ref>Websters New World College Dictionary. 4th ed. 2001.</ref><ref>Duda, Rudolf and Rejl, Lubos 1990. ''Minerals of the World''.</ref> Similar to carnelian is a darker and harder stone called 'sard'. The two names are often used interchangeably. Both carnelian and sard are varieties of the [[silica]] mineral [[chalcedony]] coloured by impurities of [[iron oxide]]. The gemstone has been used since prehistory.<ref>Tallon F. (ed) ''Cornaline et pierres précieuses de Sumer à l’Islam''. Musée du Louvre, Paris</ref> == References == {{reflist}} [[Category:Minerals]] [[Category:Gemstones]]