Whats the story with the "Copper bearing" Sunstones?

[RedSpinel]

I havent been paying a lot of attention to the gemstone market for the last 1.5 years. But I began receiving access to the 'Gem shopping network' for several months, which I had not seen for nearly 10 years. So I start watching, and literally as I type this post I am watching 'Mike' attempt to see his Oregon "Copper Bearing" sunstones.


I have heard of sunstones before, as they are a somewhat common gem. In fact, they always seemed to be inexpensive for the most part, but most of them werent completely transparent either. But now I am seeing these yellow, orange, red-orange sunstones being referred to as "Copper bearing". But when I went and looked it up online, the description I received for copper bearing sun stones was that some sunstones literally contain tiny flakes of copper as inclusions, and those flakes are visible to the naked eye. But what is being sold here and elsewhere as copper bearing are 100% transparent sunstones that dont appear to have any eye visible copper inclusions.

Now I am fully aware of deceptive marketing terms used to sell gems at higher cost. Obviously one of the more expensive and sought after gems is the "Copper Bearing Tourmaline". I remember seeing people advertising just about any tourmaline as copper bearing from time to time, regardless of its color. Same with the term "Paraiba". Not only are non-paraiba tourmalines advertised as paraiba, the term is used for other gems as well, in order to increase the desirability and value. Same with the term "Padparadscha".

I am assuming that the term Copper bearing is being used to increase the desirability of these Oregon sunstones. I have to say that many of the stones he is selling are absolutely gorgeous! The orangey ones are among the most beautiful orange colored gems I have ever seen. They have wonderful luster and brightness. Most are eye clean. He says that the GIA claims that the red-ish sunstones are the most sought after by the general public, but I think the more pure orange are brighter and prettier. The ones Mike has been selling are pretty much all very well cut with no windows, and very few if any inclusions. But he is selling them for what works out to around $700 to $1,000+ per carat. I am seeing him selling most in rings, and he will sell a yellow one for less, but not much less.

I did some research, and if you look at the rough, you see that the vast, overwhelming majority are colorless, and even the rough that contain the orange, yellow, red-ish colors are only colored at the very center of each rough stone, with the outer majority of the rough being colorless, so they must cut their way to the very center of the stones to get at the colored part. Even then, some obviously are cut in such a way that they include color zones where part of the gem is colored and part colorless. They try to hide the colorless part, and they probably include it in the gem in order to increase weight. Several of the sunstones that Ben Ko has been selling are like this.

This copper bearing sunstone phenomenon is a new one for me. Every sun stone from Oregon being sold by those 2 dealers at GSN are being sold as copper bearing sunstones. Here are the questions: Are real copper bearing sunstones supposed to contain visible flakes of copper as I had read online, and are the dealers at GSN being deceptive with their use of the term copper bearing? What is the real retail value of these gems if they are really nice, well cut, etc? Are they really as rare as these guys make them out to be? When did these top color sunstones hit the market, and is this a new-ish gem discovery aside from standard sunstone, or are they just now becoming more popular due to effective marketing, spin, and fancy trade names?

 

[T L]

I am assuming that the term Copper bearing is being used to increase the desirability of these Oregon sunstones.

+100

BTW, I watch GSN, and I've seen sunstones like theirs elsewhere, but other vendors don't tout them as "copper bearing."

The guy who sells them is always screaming, and has the most annoying voice. I have to turn the volume down when I watch.

 

[Michael_E]

The sunstones from Oregon do often have platelets of copper inside of them. This is called "schiller" and a search for that term will yield far better images than I can provide. Basically the copper platelets form microscopic mirrors inside the stone and along the cleavage planes. When you tilt the stone the copper flashes in an attractive way, sometime forming designs such as spires and pinnacles on a red background. Is it rare? Not really. Is it expensive, definitely not. The rough schiller costs around $2 per carat at the low end, though really large fine examples can be many times that amount. The copper bearing pitch is probably an attempt to tie these low value stones to the much higher value copper bearing tourmalines from various areas in the world. Since their is no actual relationship this advertising is a bit misleading, if technically correct.

 

[PrecisionGem]

The prices of good Oregon sunstone has gone up a lot the past few years, both rough and cut. A few years ago I could buy a nice rough with a red center, for $20 for the stone. That same stone this year in Tucson was $100 or more.

 

[Alnitak]

In regards to the original question, the copper is a crucial component. There's a LONG back story here involving lawsuits, undisclosed treatment of gemstones, etc. Too long for here. But here's some key things to know:

With the exception of a recent find in Mexico, the sunstone found in Oregon is the only sunstone in the world known to have copper in it. Why is that important? Well, its not just the schiller, or little platelets of copper. Rather, it's the unique suite of colors that are created in the gemstone as a result of the copper. These range from the lighter coppery oranges and reds to bright "fire engine" red, deep blood red and even more rare greens and teal blue-greens. The best gems have little to no schiller. They are typically pleochroic and show different colors or different tones of color on different axes and some are "watermelon" with a rind of green or blue green around a red core.

Like nearly all colored stones, the zone of color is typically placed in the culet or center of the stone to flood the whole stone with color. If you know what to look for you will often see this done with sapphires, amethysts and other gems that have zones of color. This allows for a larger gem with overall good color without sacrificing too much rough.

While plain straw-yellow or clear sunstone is common, copper-schillered sunstone is not--because its only found in Oregon in just a few locations on ancient lava flows (again, there is a brand new find in Mexico, but it does not have the colors that have been found in Oregon). That said, copper-schillered sunstone is vastly more common than totally clean colored gem rough. Totally clean gem rough of the most desirable colors is quite rare and can be very expensive. Top reds and teal blues will retail in the range of $400-1000/carat depending on size and color.

About a decade ago someone in China or Thailand was involved in taking colorless/light yellow andesine feldspar and diffusion-treating it with copper to create "red sunstone" or "red andesine feldspar." The big TV channel was selling it. It was represented as a new find from Tibet, or from Africa. None of which was true. It has been proven to be sham. That depressed the price of the real material from Oregon for a while, and confused the market, but things are rebounding.

Its a little soft at 6.5 on the Mohs scale, but still very suitable for jewelry (similar to tanzanite). The color is just remarkable in the best stones and for those who care about it, its an American gemstone and one of a kind. While globally rare, its common enough to be affordable and available, although its still not super easy to find. Here's a ring I just put together using a fabulous red-orange sunstone with just a splash of copper schiller. I like when there's a tiny bit to clearly link the stone to its provenance.

Jeff

 

[LoversKites]

Sunstone was never a stone I was particularly interested in. Now I am -- great info you all posted, thanks

 

[T L]

I have a 9 carat sunstone cab with schiller, and I always wanted to set it with a prehinite cab I have around the same size. The prehinte looks like a minty green moonstone. I think they're very pretty gems. Both gems were extremely affordable.

 

[Lee Little]

Yep, the Andesine scam is pretty much old news now so the price of the real Mc Coy is gaining ground fast.