About: http://webisa.webdatacommons.org/22173243

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	They had some idea that the mines used magnetic sensors, so everyone removed all metal, including their buttons, and made tools of non-magnetic brass.
http://www.w3.org/ns/prov#wasQuotedFrom	thefullwiki.org