About: http://webisa.webdatacommons.org/397189874

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	These use substances such as iron oxide, tree resin and Silly Putty to sculpt the mirror surfaces into shapes approaching mathematical perfection, initially rubbing away at most one micron, one thousandth of a millimetre.
http://www.w3.org/ns/prov#wasQuotedFrom	aeon.co