About: http://webisa.webdatacommons.org/239014780

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	Particulate silver, the ubiquitous photographic image-forming material both the nineteenth and twentieth centuries, will react dramatically to atmospheric contaminants such as hydrogen sulphide and peroxides.
http://www.w3.org/ns/prov#wasQuotedFrom	nga.gov.au