-- Mohs hardness rating: 5-6.5
-- Found in Australia, Brazil, Slovenia, Central America, Japan, Russia, US
The opal, known as "The Queen of Gems," sparkles mysteriously, a rainbow of colors reflected in a milky sea. Its name comes from three sources: Sanskrit "upala" (precious stone), Latin "opalus," and Greek "opallios" (to see colors change). Understandably, it has been treasured for its beauty throughout the history of the world.
Historically, the gorgeous opal was credited with aiding the eyesight and strengthening the blood of its wearers. Opal jewelry was also treasured by blonde maidens in Central Europe as a magical preserver of hair color.
The opal has a dual history, however; in past centuries, the opal was blamed for bringing on the evil eye and for generally bringing bad luck. Perhaps this can be explained by the fact that the opal is composed of silicon oxide and contains some water. Thus, it is much more fragile and brittle than members of the quartz family and can crack unexpectedly, especially if worn every day or in extreme temperature changes.