In Greek language, in the first century before Christ, the gemstone was known as ?opallios?.
In Indonesia Opal was known as ?Kalimaya? a name also derived from the Japanese word ?Kali? meaning a ?river? and the Sanskrit ?maya? meaning ?an illusion? and hence the stone was a ?river of illusion?.
The Aztec name given to early Mexican Opals was ?vitzitziltecpatl? meaning ?Hummingbird stone? as the color change of precious opal was likened to the changes of color seen in the birds? plumage