About: http://webisa.webdatacommons.org/316712806

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Typically, in the centre of the rock, there is a cavity in which crystals often form.
http://www.w3.org/ns/prov#wasQuotedFrom	natures-artifacts.com