About: http://webisa.webdatacommons.org/146075495

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	ve grinding large masses of ballast are required (such as balls or other grinding media) to exert the necessary impact forces and also due to the large contacting surfaces.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com