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 Geoscience Australia

Opal - Wikipedia

Opal-An (hyalite opal) from Zacatecas, Mexico. (A) Natural light. (B)

e-Rocks Mineral Auctions

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

Opal, Properties, Types & Uses

Common Opal: Mineral information, data and localities.

Opal - Wikipedia

Red Opal Root Chakra Healing Crystals and Stones Rocks Mineral Specimen

Boulder opal

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-AN”) / (variety - “Hyalite Opal”) / (“Blood Vessel Opal”) / Locality - San Luis Potosi, Mexico