Sunday, June 11, 2017

Black Opal Buyer's Guide: Beware of fakes and treated stones!

If you are thinking about buying a black opal, this guide is for you and you NEED to read it.  For those of you looking to buy a rare black opal here on ebay, there are a good number of natural, true black opals for sale.  
However, there are also an untold gazillion number of stones offered for sale as natural black opals which, in fact, are opals that have been smoked and/or treated and are not worth what natural untreated black opals are worth. These smoked/treated opals are in many instances offered for sale by sellers with very high and good feedback. These treated stones are worth pennies on the dollar, unless of course you are properly informed and still want to buy it, then it is worth whatever someone is willing to pay.   

 I have a great many friends who are and/or have mined and dealt in Australian Opal, and myself have dealt in and cut natural black and other opals, and I have also mined and dealt with Black Opal from Virgin Valley, Nevada, in the United States, for years.  Thus, I have seen and handled a lot of opal, and have enough experience to write my findings on the matter to educate you.   

 The purpose of this guide is to inform you of these facts and give you the knowledge to make informed decisions. You should educate yourself in this regard to know what is real black opal from what is fake or treated.  Keep in mind that true, natural precious black opals are very rare, and until very recently were found in only two deposits in the world:  several fields in Australia, and Nevada in the United States.  In the winter of 2014 GIA reported about the discovery and occurrence of natural black opal from Ethiopia in the Winter 2014 issue of Gems & Gemology Magazine ( GEMS & GEMOLOGY, WINTER 2014, VOL. 50, NO. 4). This deposit is south of the Wegel Tena (Welo) opal mines.  Keep in mind that true black opal will be expensive, starting at $40.- USD per carat for low quality cut stones, to $13,000.- per carat (or more !) for the highest quality cut gems.  Source:  Opal Identification and Value (Revised Ed., 2003, by Paul Downing/Majestic Press, p.100).   Black Opal from Australia, and particularly the Lightning Ridge fields, is the most valuable and reputable around.  Second to that is the dark greybase opal from Mintabie in South Australia.   The Virgin Valley black opal from Nevada in the United States is considered to be the most beautiful, but rarely produces gems that are stable and won't crack in time, and thus most (but not all!) Virgin Valley opal is considered to be specimen material (that can still cost many thousands for a stone in a wet dome).  Dark caramel and chocolate colored stones have been found in Ethiopia at Shewa, but these opals for the most part are not "black" and have the same stability problems that the opals from Nevada do.    By now everyone knows of the breathtaking opals that are coming from Wello (aka "Wollo") Province in Ethiopia.  These are mostly crystal, fire, cream, and white base opals.  What has been occurring for some time now is that these Ethiopian Opals are being dyed and/or "Smoke" treated to enhance the background color (changing it from light to dark black) and are being passed off and sold as "natural" black opals.  This is not the case!  To see what natural opals, (including black opals) look like, and their comparative pricing, see my " Beautiful Opals" Collection here on Ebay, which features natural opals that I have found across Ebay.  I have also created the collection "Natural Black Opals."  This will give you an idea what you are looking for.  To see what treated, smoked and/or dyed black opals look like, see my "Smoked & Treated 'Black' Opals" collection here on Ebay.  You can see the difference in the base color and patterns (and price!!!, in most cases).  You can read one of the online lab reports by searching on google for: 

"   stonegrouplabs SmokeTreatmentinWolloOpal.pdf   " 

which should turn up the report, or simply google search "ethiopian smoked black opal" which should turn up results.   It is not my intent to harm any sellers by posting this information, but rather to provide this information to the public so that they can make knowledgeable decisions about what they are purchasing.  Many dealers are offering these smoked/treated opals as natural black opals (some going so far to offer free lab certificates with a purchase) and you need to be aware of the facts so you know what you are buying.  Keep in mind that now there are natural black opals from Ethiopia, but don't expect to get real Ethiopian Black Opals cheap; natural black opals, regardless of origin, are going to be costly.