Some Questions Received About Black Opal :

Q.  What is it that distinguishes a black opal from other opals ?  Can an opal be dark and not be a black opal ?

A.  If opal sits on a black base, it is classed as a "black opal".
If the opal  sits on a dark grey base  then it may be classed as a semi-black opal.

A lighter grey base would class it as grey opal.

True black opal is the rarer of the species but the value naturally depends on the quality of the gem opal.

Rare patterns make them even more valuable e.g. harlequin patterns with primary colors of red, red with royal blue and so on. (My carved Black Opal Pendant is a natural black opal without any backing.)

What should matter to the consumer is the quality of the opal, with the clarity and play of it's gem colors, whether the base is black, semi-black, grey or crystal then becomes a matter of choice for the individual.


One may have a black opal with average gem color compared to the same sized grey base gem stone that has brilliant gem color - the grey based gemstone would win hands down i.e. much more valuable because of the
quality of the gem opal.

Other factors come into play e.g. intensity and brilliance of color followed by the base tone which goes from black (with it's sliding scale from N1-N4 etc.) then semi-black, dark grey, grey and light-grey to white.( N5-N9)

Top gem crystal is a different category again.

At the top of the scale is the finest black opal; it is rare and can range  up to $50,000 per carat (for larger and very rare patterned brilliant gems). 

Next on the price scale would be the finest gem crystal opal.



Q.  Is geography a factor ?  Does the opal need to be from some particular region to be called a black opal ?

A.  No, geography is not a factor - black opal is classified by it's black base wherever it is found.


Q.  Comparing two opals,  both with comparably dazzling color flashes, why is a true black opal better - because of the base it is attached to when it was mined ?

A.  Yes

Q.  Is it more valuable because of this definition that has been attached to a black opal or are there practical issues?

A.  Yes, it is more valuable because of the base it is attached to when mined, and the practical issue here is that the natural black backing  intensifies even more  the brilliance of the colors.
 
It is a rare occurance having quality gem opal forming with the natural black base stone.   Hence the price tag!


Q. Is there a standard like the colors D,E,F,G,H, etc. in diamonds where the  opal stone is compared to a known standard ?

With this one, there is a priority in the colors.   Basically, it goes Red..Royal Blue..Green.., in that order but.... there are so many combinations with the colors, you cannot pin it down to an exact science, unlike diamonds!

Color intensity, patterning and play of color all come into play.  Usually though, the brighter the red, the more valuable the opal gem.

Even out at Lightning Ridge,, a miner would take a valuable gem to three separate valuers to get an "average" on the worth of the opal gem as each valuer would price it differently - it just is that each individual will view it a little differently.

The N1 to N4 on the  Opal Scale is the backdrop for the darkness tone of the black opal,  which then determines which category the tone may fall within.

Translucence is how far you can see down through the color layers.

As an example, we will take black opal.   The gem bar may be very bright and sits on a black base but it may also be very translucent, enabling one to peer down into it's depths.

However,another black opal may have brilliant colors but may be much more dense in tone because of the depth of the black tone throughout the gem colors themselves,  and you will not be able to see much further than   the surface play of  color - therefore it would be difficult to class it as translucent.

Carat for carat, color for color, the more brilliant and more tone dense the color (not necessarily translucent) then the more valuable the Black Opal would be.



Q. In jewelry, why is a solid opal better than a doublet of identical appearance - (other than psychological). I mean, people never take jewelry apart to see what's inside anyway.

Some of the beautiful opal jewelry I have seen is inlay. Does it make any difference to the wearer if that inlay is a solid opal or just a thin slice?  Is it a durability issue?


A. In jewelry, it is the quality of manufacture (and the gem opal used) of the doublet, and/or quality of the construction of the inlay work that is all important.

Very high quality manufacture of opal doublets for fine jewelry means jewelry for life and has a sound investment value as well.

If a solid black opal or solid crystal opal is set in jewelry it would be wise to leave the back of the jewelry open to prove the authencity of the gem being sold and genuine.  How else could you prove that it was a genuine black opal/solid gem crystal unless you could view the back AND sides of the opal gem?

Ah, inlay work - yes, sometimes it is a durability issue where people use opal better suited for triplets (which uses a very thin slice of opal) rather than inlay material and also the kind of adhesive that they may use.

The thicker the opal slice the better for increased strength and durability.

With beautiful and bright inlay work to have reasonable thickness AND brightness of color, one must work with opal of a higher quality to have the desired outcome.

High quality gem doublets and high quality inlay opal work do have very sound investment value.
 
On a couple of my trips out to Lightning Ridge, I have seen some amazing examples of inlay and mosiac work with price tags to match!





Note from Peter :

It is very unfortunate that there have been many individuals who have misled the greater community about Black Opal, and have done the wrong thing by the industry and people. 

Even now so many people advertise black opal triplets.   Once it is a triplet, it loses all claim to being black opal.

Another one is black opal doublets - this one really is a point of contention.  Only and only if the opal sits on black potch naturally (even if thin) and then it is bonded  to other material, can it be classed as a black opal doublet.

Simply being opal from Lightning Ridge and glued to black potch does not make the piece a black opal doublet!

To call it a black doublet opal however, is a "play of words", but it is acceptable in some cases.