About: http://webisa.webdatacommons.org/367718541

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	Chalk is a soft, white, porous sedimentary rock, a form of limestone composed of the mineral calcite.
http://www.w3.org/ns/prov#wasQuotedFrom	bio-medicine.org