About: http://webisa.webdatacommons.org/336520173

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 a material having a small surface-roughness, a variety of glasses used for magnetic disks or optical disks, polymeric material such as a polycarbonate, metals such as Al, Si substrates, or carbon can be used.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com