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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	Only a few minerals are harder, including diamonds, rubies, sapphire and topaz.Petrified wood would also give those minerals a run for their money in comparisons of color.
http://www.w3.org/ns/prov#wasQuotedFrom	vineyardgazette.com