The Questionable Andesine Story

Jeff R Graham shares his opinions and thoughts on various topics in Just Ask Jeff. See what his answers are to the continuing questionable Andesine story..?

13 Minute Read

Picture of a sign with rough/andesine story

I want to clearly state that these are my opinions and observations in this article. I am sure some people will not agree with me and have differing opinions. But for what they are worth here is what I think on the subject of Andesine. In particular the Chinese and Congo material.

Is there such a thing as real Andesine? Yes, there is. I have seen legitimate material from well known miners and mines here in the USA. The material I have seen is from Oregon and been tested as Andesine. It is important to realize that there is some real material and that the Oregon Sunstone and/or Andesine needs to be judged seperately from the majority of the Andesine on the market that is questionable and coming from outside sources that are not verified. The Oregon Sunstone mines have been long established and are legitimate producers of material. That being said I am of the opinion that there is a skunk in the wood pile and much of what the gem market is selling as "natural untreated" Andesine stones is not what they are claiming.

*** November 2008***
The vast majority of the Andesine stones on the market now been proven and admitted as being "Enhanced" and "Diffused". The major TV marketers after settling many law suits out of court have now labeled their material as "Enhanced". This is a polite word for Treated/man-made color in my opinion, but at least now the material is being sold as treated.

What is my opinion and what do I think? In my opinion most all of the Andesine I have seen in the market is treated and definitely not from the supposed localities they claim. I am of the opinion that they are using a combination of heat, radiation, and diffusion to obtain the colors, red and green mostly. This is of course on material claimed to be natural and being sold as natural. If this material were proven and known to be treated. The price of Andesine would tumble down to the basement and be similar in price to other man-made colored materials, at least I think so.

I will point out that at this time Jewlery Television is now saying (Feb 2008) that the material is heated and that "testing" for other treatments is inconclusive. They say they have recently discovered that heat is being used. I have said heat, irratiated, and diffusion from day one years ago (2002). Why it has taken this long for the heating to come to light and be admitted? I do not know. As for the irradiated and diffusion? We will have to wait and see. What this really means in my opinion that yes the material is heated and that there is no way to know if the material is also treated in another way. At least yet. So they cannot tell if the Andesine has been, and is being irradiated or diffused. In my opinion it is being irradiated/diffused at least part of the time and probably heated many of the times.

As I said heat is now being admitted on the Andesine. The suspected treatments are heat, irradiation, and diffusion of some kind. The treatments could be one of these three, or a combination of any or all of them.

Note: Please keep in mind this is what I have been told by my Thai friends and cutting houses, it is second hand and I cannot prove it. But this is what they tell me. I have been told the treatment is heat, then tumbling the rough to "open" up the material, then heat and copper injected under pressure. This process is repeated several times to get the color.

Jewelry TV blog with video - This blog was removed and never put back up… the claim was website improvement. Gee what a surprise. Also JTV makes the claim that "heating" is a common industry practice and that it does not change the value of the gem stone (Andesine) because the color sets the price. Yes, heat is a common practice in the gem industry this is absolutley true. But I disagree that the value of a heated stone is the same as the value of a natural unheated stone. This is simply not the case in my opinion.

A natural unheated stone is always more valuable than a heated stone. Look at any natural unheated Sapphire price verse a heated Sapphire. The natural stone will often be two (2x) to four (4x) times the value of the heated stone in price and there is a premium on unheated and untreated stones. In some other types of stones heating may not effect the price as dramatically, but it does usually effect the price.

The treaters maybe starting with colorless material, schiller, or even some light color. I do not know. But there are just too many unanswered questions and things that make no sense to me.

Note: I would point out that the supposedly watch dogs of the gem industry are very, very quiet and rolling over and playing dead on this entire subject in my opinion. This is either the "watch dogs" playing "Do not ask, do not tell…" or some thing a lot more dishonest.

One of the major problems of the claims that the Andesine material is real. Is that there is just rumor and speculation about where the material is really mined. I hear all kinds of stories about where it is mined… the "Congo" or it is mined in "China" and so on. The bottom line is there has never been any verification by any reliable independant source, at least to my knowledge and satisfaction.

Note: My sources for Labradorite in Mexico (where mines produce a lot of this material) tell me that they are selling all their production to China, with the rare exception of a bit of the large stuff I buy along with a few other USA buyers. I have no way to verify this claim, but it is interesting to note and would not surprise me. Are they treating the material or just cutting it as gold? I have no idea.

Another major issue with Andesine is that there is virtually no rough, any where. This goes against every thing I know about mining and the gem stone business. THERE IS ALWAYS ROUGH. Maybe not good facet material but some kind of rough in the markets is always around from any legitimate mine location

By this I mean. I do not care how tightly controlled a mine is there is always, and I mean always, at least some small rough and lower grade material is floating around in the gem stone mining and selling regions. On Andesine there is none, nada, zero, zip. This to me is a very large red flag.

Another issue. NO MINE produces just facet grade rough. It is not possible. All mines produce lower grade rough that is usually cut into cabs and carvings. All mines also produce mineral specimens, crystals, or just interesting pieces that are sold and traded by the mine and miners to make money. Believe me the cab and mineral business often is more valuable to a mine than the facet grade material because there is so much more lower grade material produced in any mine than facet grade clean gem stones.

Andesine? No I have never ever seen a single mineral specimen. Why? I have never seen a single cab. Why? I have never seen any facet grade rough either up until this year. See the picture below. These pieces are virtually the first rough of supposedly natural Andesine I have ever seen or been able to get pictures of.

Note: I asked permission and so did several other people like me at the time. We were given permission by the owners (there were several venders) of the stones in the pictures to photograph them. On a side note when we snapped a photo on the above paper claiming "no heat", "no treatments" the guy got very nervous and snatched the note back from us and turned it over so it could not be photographed again.

Left: A picture of supposedly natural untreated and unheated Andesine rough.

When I looked at these two pieces of rough Andesine the first thing that came to mind was "melted". Unheated? Yeah right. In my opinion this rough had been heated so hot that the crystals were almost melted. There were burn spots in cracks of the rough and the edges were rounded from very high heat.

How do I know? Lets say I have personally heated Sunstone to these tempatures and been doing various experiments. These experiments and my conclusions will be in another article at a later date.

Note: When examining some of the faceted stones I could clearly see melted schiller lines, another obvious sign of heat.

Lets say I know "melted" when I see it. It is pretty obvious. What other treatments were done to this rough? I have no way to know… But as I said I am of the opinion that there are other processes being used to create color besides heat on at least some of the Andesine being marketed.

Note: Any graduate gemologist with a microscope (any one else with a little knowledge) should be able to spot heating very easily. Anybody checking these cut stones should have seen the heating right away. Why the large marketers (TV in particular) did not spot the heat or admit it years ago? That is a a good question. I do not know.

Above: A picture of faceted Andesine. Please keep in mind that these pictures were taken under fairly poor lighting and under tough circumstances. Again we did ask for and receive permission from all the owners before taking any pictures.

Still another issue. NO MINE produces one color and no natural faceting material is all this constant in color… In my experience no two stones are ever alike, even if they come out of the same piece of stone in most cases. Some stones almost always vary in color and tone at least a little bit.

Note: I am talking about the Andesine stones that I saw at the Tucson show, in these pictures 2008.

Note: Also variance in color does not necessarily mean no treatment, treatments, heat and so on can vary dramatically. So treated stones can all look different depending on what has been done to them from batch to batch. My point here is these stones all looked the same. Natural stones almost always vary in color and tone. There is no current way to tell if the stones have been treated other than heat.

Note: I will say that heat treatments on the stones I examined was very obvious in the rough as well as cut. The schiller copper lines in the stones looked almost erased (melted). Look at some pictures of silk being heated out of Sapphires and that is exactly what the schiller looked like after heating in these Andesines. The heating at least in these stones was really obvious. Heating on stones like this is almost always easy to spot and any first year gemologist should be able to catch the heating with a microscope very easily.

Look at the stones in the tray in the picture above. Look how closely they match in color and tone. There are no light ones, no dark ones, no pinker ones, no orangey ones… In my experience and opinion natural rough just does not occur this way. I think there is some thing being done to these stones. But go look at any natural gem stones and line them up, even if they are from the same mine and the same material you will see some variations in all the stones. Getting a good match in most faceted stones is hard to do. Not in this Andesine.

Left: A picture of supposedly natural untreated and unheated Andesine faceted stones.

Look at all the stones. They are the same color, look below at the next picture it is a different vendor. But the stones are all the same. All the cut Andesine we saw was supposedly from a mine in China. The guys selling it were of course Chinese and Thai. There were literally thousands of cut stones all the same tone and color. All the stones were the same price per carat?

Interesting? When was the last time you saw stones all the same color (exactly) and the same price per carat? Well my answer and opinion is when the stones are all costing the same and treated. There is no variation so there is no stone better or worse than any other. All the pricing is the same. Pretty interesting wouldn't you say?

Left: A picture of supposedly natural untreated and unheated Andesine rough. from another vendor.

OK, the bottom line here is that there maybe some genuine Andesine that is untreated in any way.

But the majority that I have seen and looked at appeared like it has some serious issues about treatment and is being sold under questionable conditions in my opinion.

Unfortunately the gem stone market is a buyer beware market and to some extent always has been. In recent years I am sorry to say in my opinion the gem stone market with all the various treatments and man-made stones being dumped into it has become a mine field for the average buyer.

The supposed watch dogs are all feeding at the table of the big interests and the ones that are not, are either not effective or not paying attention. It is a pretty sad state of affairs and in my opinion there seems to be a lot of very questionable things going on behind the scenes that are not good for the customers and the business.

I do not sell or deal in Andesine and I will not until I see some real proof that the material is natural. Now I really do not care if they sell treated material or man-made of any kind for what ever price they can get. But if the material is treated and/or man-made… They need to identify the material in question as treated and/or man-made and sell it that way.

Just my opinions. But buyer beware. I am not buying any Andesine until some serious questions are answered.

April 18, 2008 - There have been some reports and testing by ISG (International School of Gemology) that confirms treatments and they may have found a test for treatments.The evidence is pretty conclusive that the majority of the Andesine that TV sellers and others in the commercial market have been selling is not only heated, but treated as well and may not even be Andesine.

On tested samples from commercial (TV) suppliers they have found that the RI (Refrective Index) of the treated matertial is consistantly different than known real stones. This RI difference seems to be very consistant and may turn out to be an easy test for checking treatments. Also they found that the inclusions under a microscope were not the correct type for the material to be Andesine as and they found fractures and inclusions that had coloring agents in them as well.

Here is an except from an article on their website.


Colored Stone Magizine - Coming to a Court Room near You: The Labradorite Litigations

Jeff R. Graham

The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.

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