Ethiopian Opals Grading And Patterns
Ethiopian opal is one of he most diverse and spectacular types of opals on the market today. Since this type of opal is new, there is no industry accepted way to grade this type of opal like there s with the black opal. Black opal is grading in terms of blackness, the brightness of the color and the pattern.
Similarly, Ethiopian opal is also graded on pattern and brightness, but the body tone of the stone does not play a huge role in determining the final value.
There are many unique patterns to Ethiopian Opals and on Opal Auctions the descriptions have to be accurate. One of the most popular patterns in Ethiopian opals is a naturally formed potch line with web inclusions known as honey comb pattern. This pattern is very rare in any other type of opals. These honey comb shapes are also known on occasions to have brighter or different colour than the surrounding opal, this is also a rare occurrence in nature.
Color And Brightness In Ethiopian Welo Opal
This refers to the fire within the opal. The translucent internal fire of these Ethiopian opals have properties that make the fire look 3D. This 3 dimensional colour aspect is rare in most opals. It looks like fire has been captured within the opal.
Many Australian black opals have hidden colour spectrum patterns deep within the opal so a blue opal can have hidden translucent colour bars with violet or purple hues that cannot be directly seen by the naked eye. Ethiopian opals have vivid translucent colour bars and patterns that are strikingly bright and are visible with the naked eye.
Ethiopian Opals are valued based on their bright flashes of fire colour. The brighter and more intense the color, the higher the price of the opal. Stones with red flashes are rarer than the other colors while the green and blue flashes are more common.
Treated Ethiopian Black Opal
I was at the recent Bangkok gem show where I saw large amounts of Ethiopian black opal being sold with gem reports saying its natural. New findings have shown that most, if not all, of the “black” Ethiopian opal now seen in the market is not what it appears to be! It is either treated by innovative new “smoking” techniques to obtain it’s black-opal appearance. As this opal is hydrophane it seems to respond to smoking well. Smoking techniques are not new where opal is concerned, but what is now being used on the Ethiopian opal introduces a new twist to the old smoking method, which is why the treatment was missed by respected gem-testing laboratories.
The old technique was used on low quality opal, such as Mexican hydrophane material, to darken the colour of the base material, which causes — by contrast — a more fiery play of colour. It was done simply by wrapping the opal tightly in brown paper, placing it in a covered container, heating over medium heat until the paper is completely charred, then cooling and washing it. The result was a much prettier opal!
The other treatment that is common with Ethiopian Opal is altering the body color of the stone with dye. Some stones can be find to have a bright pnk or purple body color which has been artificially placed into the stone.
These are the only known treatment so far for Ethiopian opal and it greatly reduces the price of the stone. On Opal Auctions any treatments must be clearly stated. If you have any doubts remember to use our opal Sheriff service to get a second opinion.
The only other thing to be aware of is the fake Ethiopian opal that is on the market today. Read our article on detecting fake opals to help arm yourself with the knowledge needed to correctly identify fake Ethiopian opals.
Pattern In Ethiopian Opal
Ethiopian Opal has a wide range of beautiful patterns and shapes from oval to free-form. Black Opals from Australia are well documented with unique patterns from Mackerel to Harlequin. Similar names have been adopted to describe Ethiopian Opals. The most highly sought after and expensive pattern is the honey comb pattern.
Broad Pattern Crystal
Patchwork Rolling Flash
Hexagon Honeycomb or Fish Scale
Pin Fire Crystal
Neon Flash Pattern
Welo Broad Flash
Rainbow Pattern
Broad Patchwork
Multi Chaff Fireworks
Broad Flash Fire
Floral Eyes Pattern
Fire Cloud
Welo Patchwork Harlequin Pattern
Harlequin is regarded as the rarest pattern in the opal industry with Ethiopia having its own unique pattern-honeycomb Pattern. Honey comb pattern is the most sort after pattern on cabochon Ethiopian opal. Many opal miners will never find one of these patterns in their lifetime of work.
True harlequin pattern is a mosaic broad pattern, angular close set of colours. Floral patterns are sometimes called floral harlequin but Welo Floral or Welo patchwork would be the correct naming for these gem Ethiopian floral pattern opals.
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