About: http://webisa.webdatacommons.org/450782573

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	as Cu, Ag, Cr and Au, or alloys mainly composed of these metals are preferable.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com