About: http://webisa.webdatacommons.org/25239589

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	Alternatively or in addition, fillers such as silica may be added to increase the hardness.
http://www.w3.org/ns/prov#wasQuotedFrom	google.es