Most stones are hydrophane- highly hygroscopic. These are extremely rare and we didn’t get an opportunity to examine one by ourselves. In general Welo opal exhibits a transparent to translucent body of white, yellow, orange or brown colour.Īccording to some dealers black opals have also been found. Oiling has been attempted as well, but it was quickly discovered that it has a detrimental effect on the play of colour. Ethiopian material can also be fracture filled or coated with epoxy resin and that would seal it against the water, thus preventing the hydrophane character from being an issue. It produces opals that may be regarded as natural without appropriate testing. This treatment has been reported as stable with colour evenly penetrating whole stones. Most telling however, is 1150 cm ˉ1 peak in Raman readings, indicating an amorphous C-O bond. Stones produced this way strongly resemble natural black opals, but can be recognised by the colour concentration in cracks and burn marks. Another process relying on porosity of Ethiopian opal is smoke treatment. So far the colour tends to seep out during subsequent hydration, possibly because appropriate dye has not yet been found. Welo opal is not commonly treated but due to its porosity it is susceptible to being dyed and first experiments in that direction had already been conducted. It makes free-form cutting and carving more appealing with this gem. This causes a low yield during cutting, as one must grind deep into the stone to obtain a traditional cabochon shape. This opal rough developed black “skin” accentuating its play of colour.Įthiopian opal often comes in irregular shapes, occurring in veins and masses with sharp edges and the host rock often going deep into the opal mass. Bringing us to a conclusion that the whole opalization process occurred between those two volcanic events as no other layer,above or below, shows any signs of opal presence. The whole Welo opal deposit is contained in just one of these tuff layers, in cavities between volcanic debris. Geologically the region is composed of a horizontal layers of volcanic basalt and pyroclastic tuff. The situation has improved after the Ministry of Mines and Energy initiated a series of training sessions and provided some basic safety equipment. Rough terrain conditions, coupled with a lack of mining experience caused numerous accidents in the past with around twenty people dead so far. It is probably one of the reasons why only rudimentary extraction techniques with simple hand tools are used. Inaccessible to vehicles or animals, miners are forced to carry all the necessary equipment themselves each day. At about 10000 ft above sea level local miners must descent a 1000 ft from the top of plateau into the canyon via narrow sharply descending footpaths. There aren’t many items for men in our collection of ethiopian opals, as most of the options available are for women.Opal bearing cliffs with rock layers visible.ĭeposits are not fully surveyed yet, with all current production extending over a couple of kilometres along the edge of a river canyon some 17 kilometres north of Wegel Tena. There are many oval cut, cabochon and mixed cut ethiopian opals for sale. There have been many well-made iterations of these items over the years, but those made by Ruchi New York, Sunita Nahata and Syna Jewels are often thought to be among the most beautiful. Our collection of ethiopian opals includes designs that are universally popular, but Contemporary and Modern styles, specifically, are sought with frequency. Our inventory has long been popular, and it includes earlier versions that date to the 19th Century and newer variations that were made as recently as the 21st Century. Our selection of items includes 24 vintage examples as well as 283 contemporary versions. These distinct designs - crafted with great care and often made from Gold, 18k Gold and Yellow Gold - can elevate any look. Browse a vast assortment of ethiopian opals for sale on 1stDibs.
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