Opal: Mineral information, data and localities.

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

Opal : Properties, Formation, Uses and Deposits » Geology Science

Onyx Opal: Mineral information, data and localities.

e-Rocks Mineral Auctions

Green Jelly Opal (rare color and locality)

Opal, Peruvian Blue - Peruvian Blue Opal is a mystical dream the earth has blessed us with. The energy can vary depending on its locality when dealing

Blue Opal - Andean, Rough

Map showing distribution of opal bearing localities in Western Queensland [cartographic material] / - Catalogue

Opal-AG: Mineral information, data and localities.

Opal - Wikipedia

Opal Gems: Value, Price, and Jewelry Information - IGS

Opal : Properties, Formation, Uses and Deposits » Geology Science

Gold Opal: Mineral information, data and localities.

Rare $675,000 opal makes public debut

Opal: The mineral Opal (black, white, fire) information and pictures