This gorgeous variety of Opal displays a multitude and fascinating 'play of color'.
The Welo (Wollo) Opal of the Delanta region is what is most often used as stable, precious Opal in jewelry. The stones come in a variety of translucent bodycolors of white, blue, yellow and natural grey to black. The patterns can display broad flash, speckles, and a desirable, unique scale like appearance.
Ethiopian Opal is formed in Volcanic tuff. It is a type of 'hydrophane' opal, highly absorbent to liquids. Immersing this material in water will turn a translucent stone to a transparent, clear like material.
This is part of the challenge of cutting Ethiopian Opal, but with a little patience, the stones come back to their vibrant appearance.
In order to preserve the natural beauty of the stone , because of its absorbency, it is best to keep it away from any harsh chemicals, dyes and oils.
Another variety of Ethiopian Opal is 'Chocolate Opal', mined in the Shewa region. These nodular, rhyolitic specimens display embedded precious Opal against a rich brown bodycolor. This material is prone to crazing, and unsuitable for cutting. However, there are exceptions and few pieces can be cut with part of the host rock in place.