Sunday, May 17, 2015

Light, Dispersion & Color

Ethiopian Opal--- the new kid on the rainbow block
Ethiopian Opal ring by Ornella Ianuzzi

Been Around a While
Opals of all kinds have graced the earth for millennia. That's because these rainbow hued treasures were the result of ancient earth forming activity and  a bi-product of sedimentary or volcanic occurrences. Traditionally, most opal has been discovered in Australia, where the geological climate lends itself to its creation. Ancient sea creatures like spooky-magnificent plesiosaurs whose fossilized bones found in that region have also yielded opalized bone from time to time.

Mexico was the other arid region whose climate was ideal for the production of opal, including the non-play of color variety Fire Opal.

New Discovery--Old Material
But a couple of years ago. gem shows around the world began offering volcanic Ethiopian opal, and collectors have taken a shine to the colorful gems.
Ethiopian opal rough from Gemmology News

Opal is ofen found in host material looking something like this example above.The uptick in sales of the Ethiopian variety was tempered by caution due to their fragility. But in actuality, all opal, irrespective of origin should be handled with care. 

Watery Stones?
Did you know opal crystals contain a significant amount of hydration? This 'watery' composition can be up to 21% in some cases. The range starts at 3% and goes up. So opals of any kind should be stored carefully and not be exposed to excessively dry environments.

Ethiopian nodule from Opalinda



Ethiopian opals in particular are often found as nodules (see above); the result of volcanic activity. No wonder local tribal groups in Ethiopia caught a colorful glimpse of them on the ground and carved them into tools, as early as 4,000 years ago. Beautiful and functional! We like that.


1 comment:

Gareth Eckley said...

I love the ring. The chunk of rough Opal looks fabulous. Thank you for sharing Diana !