Opal - Wikipedia Main opal producing countries Opal is a hydrated amorphous form of silica (SiO 2 ·nH 2 O); its water content may range from 3% to 21% by weight, but is usually between 6% and 10%
Pictures of Opal - Black, Fire, Boulder, Blue and Pink Physical Properties of Opal Although opal has a composition that includes SiO 2, its physical properties are very different from quartz Opal also has water, which reduces its specific gravity, gives it a lower hardness, and makes it much more brittle
Opale - Wikipedia L'opale (simbolo IMA: Opl [3]) è un minerale colloidale amorfo, costituito da silice idrata (SiO 2 ·nH 2 O), semiamorfo o microcristallino, ovvero privo di struttura reticolare, infatti non si presenta in cristalli, ma in vene, noduli e croste di vari colori, spesso con iridescenze [4]
Opal Description - GIA "The Path of Enlightenment" necklace contains 180 magnificent opals from Lightning Ridge, Australia, a famous opal producing area - Courtesy Cody Opal Opal is the product of seasonal rains that drenched dry ground in regions such as Australia’s semi-desert “outback ” The showers soaked deep
Opal: Mineral information, data and localities. - mindat. org Although it is still (2007) regarded as a mineral species for historical reasons, opal is not a true mineral in the accepted sense of the word as it is variably composed of poorly crystalline material related to cristobalite and or tridymite and or composed of X-Ray amorphous silica
OPALE - definition of OPALE by The Free Dictionary Define OPALE OPALE synonyms, OPALE pronunciation, OPALE translation, English dictionary definition of OPALE ) n 1 A mineral of hydrated silica 2 A gemstone made of this mineral, noted for its rich iridescence o′pal·ine′ ) adj American Heritage® Dictionary of
Opal - International Colored Gemstone Association The ancient naturalist known as Pliny the Elder, during the first century A D , described opal as containing the glories of the most precious gems—the gentle fire of ruby, the rich purple of amethyst, the deep blue of sapphire, and the sea-green of emerald, all shining together in an indescribable union
Pierre Opale L’opale est la pierre de naissance du mois d’octobre C’est aussi la pierre donnée pour célébrer la 14ème année de mariage Le nom opale serait dérivé du sanskrit upala, qui signifie “pierre précieuse”, et plus tard du dérivé grec “Opallios”, qui signifie “voir un changement de couleur”