About: http://webisa.webdatacommons.org/183182530

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	However, they are poor in mechanical properties, such as surface smoothness, hardness, tensile strength and wear resistance.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com