About: http://webisa.webdatacommons.org/423174556

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	The most concentrated and most accessible fuels and minerals are mined first; thereafter, more and more energy is required to mine and refine poorer and poorer quality resources.
http://www.w3.org/ns/prov#wasQuotedFrom	blogspot.com