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

Minerals, Free Full-Text

Milk Opal: Mineral information, data and localities.

Precious opal (Virgin Valley Formation, Middle Miocene; Vi…

Polished Dark Side Green Opal Standing Free Forms x 2 From Madagascar

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

Opal - The Colorful Silica

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

Opal gemstone information

Opal Geoscience Australia