About: http://webisa.webdatacommons.org/346596743

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	Of course, 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	johnquiggin.com