Lydite
/ˈlɪd.aɪt/noun
A dark, fine-grained variety of jasper historically used as a touchstone for testing precious metals.
Did you know?Lydite functioned as a touchstone: rubbing gold against it could reveal impurities because different metals left distinctive streaks on the stone.
Etymological Timeline
Ancient Greek
Greek
Λυδία (Ludía)
“Lydia, the ancient kingdom and region of western Asia Minor”
Classical Antiquity
Greek
Λυδικός (Ludikós)
“Lydian; belonging to Lydia”
Roman Period
Latin
Lydia
“The region of Lydia”
18th–19th Century
Scientific English
lydite
“A mineral name formed from Lydia with the suffix -ite, indicating a mineral or rock”
Modern English
English
lydite
“Dark jasper used especially as a touchstone for testing gold”
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