About: http://webisa.webdatacommons.org/81940940

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	If crystals are rotated or other crystals appear in the field their color will be opposite when perpendicular to the line of orientation.
http://www.w3.org/ns/prov#wasQuotedFrom	upenn.edu