ETYMOLOGY: From de hindu "upala" = stone changes the color.
CRYSTAL SYSTEM: Amorphous.
PRINCIPLE OF FORMATION: Secondary.
CLASS MINERAL: Silicates.
CHEMICAL FORMULA, MINERAL ELEMENTS: SiO2 · nH2O.
HARDNESS: 5.5 - 6.5 on the Mohs scale.
FIELDS: Australia, Mexico, Peru, South America, Honduras, Britain, Slovakia, Canada, USA.
MINERALOGY: The group Opal distinguish between nobles opalescent opals, opals red yellow fire and common opals. The properties vary considerably. The opal is secondarily formed as a result of solidification of silicic acid gel by dehydration. Since silicic acid gel forms droplets silicon dioxides microspheres are formed. (20% water and gas). The opal color play is due to the phenomenon of light refraction in the microspheres of cristobalite.
MYTHOLOGY: The white opal is also called Opal porcelain, opal opaque milk, in Greek mythology was said to come from the tears of the fate of Zeus after the victory over the Titans. In India is the goddess of the rainbow solidified in stone when he fled from the gods angry. Opal cristobalite has small areas included in a mass of hydrated silica gel, when these small areas are of equal size and an ordered three-dimensional distribution of the optical effect opalescence occurs, however when the small spheres are of different sizes and they are arranged irregularly opalescent effects not present."Big Ben", a white precious opal of over 800 grams, more than 4,000 carats, was found at Rayo Ridge.
PROPERTIES: It is said that the white opal helps us accept ourselves and others, encourages communication, sharing and community, is a seductive stone that intensifies emotional states and releases inhibitions, can act as an emotional stabilizer, it said that wearing an opal brings loyalty, fidelity and spontaneity, psychologically makes the wearer more friendly and welcoming in the deal and avoid to some extent the variability of humor.
ZODIAC SIGN: Cancer.
USES: Jewellery, meditation, collection, powder is used as an abrasive.