<http://webisa.webdatacommons.org/prov/228858961>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/334960056> .
<http://webisa.webdatacommons.org/334960056>	<http://www.w3.org/ns/prov#value>	"Readily available in many countries including Italy, Greece, Israel, and Iceland, pumice is relatively inexpensive and can be disposed of without harming the environment." .
<http://webisa.webdatacommons.org/334960056>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/ns/prov#Entity> .
<http://webisa.webdatacommons.org/334960056>	<http://www.w3.org/ns/prov#wasQuotedFrom>	<eurekalert.org> .