<http://webisa.webdatacommons.org/prov/11327074>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/269822404> .
<http://webisa.webdatacommons.org/269822404>	<http://www.w3.org/ns/prov#wasQuotedFrom>	<schools-wikipedia.org> .
<http://webisa.webdatacommons.org/269822404>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/ns/prov#Entity> .
<http://webisa.webdatacommons.org/269822404>	<http://www.w3.org/ns/prov#value>	"Because the minerals are mostly fine-grained, it is much more difficult to distinguish between the different types of extrusive igneous rocks than between different types of intrusive igneous rocks." .