Heat treatment of sapphires

Sapphires have been routinely heat treated for many years. The basic concept behind the treatment is that 9 times out of 10, heating the stones results in what is generally considered a more pleasing color. Some Sri Lankan sapphire occurs nearly colorless (known as "gueda") but can turn a wonderful blue color with heat treatment. Most material comes out of the ground lighter in color than what is considered most desirable.

Most desirable, of course, is often in the eye of the beholder. Personally I have always been drawn to lighter colors in sapphires as I find they sparkle more. But, either because of an individual's preference, or because of the heavy marketing of dark blue sapphires, many people want a very dark color in their sapphires.

All colors of sapphire can be heated. Much of the yellow sapphire on the market today seems to be heated. Most pink sapphire is heated. Purples are now routinely heated (although many years ago when I started selling purple sapphires most of them were not heated).

More recently sapphires have been diffusion treated. This is usually a process where the gems are heated but another element is added into the crucibles, either on purpose, or accidentally and the element is actually diffused into the stone's structure (this is all simplified quite a bit for an easier understanding of the process). Most diffusion treatments are effectively only surface treatments. This creates a problem as if you need to repolish a diffusion treated sapphire, the color will disappear. More recently however, it seems that some material has been created in which the diffusion treatment runs almost throughout the entire stone. By introducing another element into the gem, I believe this is no longer truly corundum and I won't personally sell diffusion treated stones. One of the reasons I work with so few gem dealers now is because I need to know exactly what I am getting and I only work with people I trust to know this.

I also refuse to buy my colored stones from any dealer who is not a member of the American Gem Trade Association (http://www.agta.org/). They have more information on gemstone treatment on their website if you're interested in more information. Members of their organization MUST disclose all gemstone treatments on every invoice they write. They have been the front runner in the entire topic of gemstone treatment disclosure.

A few years ago, a plethora of orange sapphire suddenly appeared on the market in quantities not seen before. Since there had been no new mines producing the material found that could account for this, the gem trade began looking a little more closely at this material. It turned out that it was almost all diffusion treated using a new process in which the treatment went most of the way through the stones. It ended up with an almost virtual halt in the trade of orange sapphires for a number of years until proper identification methods could be researched and found. Recently orange sapphire has been reappearing in the marketplace (properly disclosed) and I was fortunate enough to just purchase about 15 cts. of beautiful natural color, unheated, orange sapphire melee (stones 3.5 mm and smaller). Anyone who would like to check out some of this material come on by my store sometime and I can show you.

Next posting: More on sapphire treatments

Pictured above: Four untreated sapphires.

Man is always trying to improve things that nature has created and gemstones are no exception. Gemstone treatments go back to ancient Egypt when they would throw agates into hot oil baths in order to quench crackle them and give them a different appearance. However, in today's world, with all of the scientific advancements that have occurred, gemstone treatments have gotten far more sophisticated and far harder to identify.

Some gemstones, like tanzanite, would not even be sold if it weren't for the treatments. Tanzanite comes out of the earth a pretty ugly brown color. It is only through heat treatment that the beautiful blue/purple color it is known for appear. Similarly blue topaz, while occasionally occurring naturally in blue, would never have gotten so popular if it were not for the irradiation/heating treatment that turns the excess of white material into blue.

Some treatments are less stable than others. Emeralds have always been oiled, or more recently fracture filled with an assortment of substances, in an attempt to reduce the visibility of the inclusions, or "jardin" that is common in almost all emerald material. Oil can leach out over time from normal wear and tear (washing your hands, exposure to cleaning agents, etc.) and the entire look of the stone can change over time because of this. Advancements in gemstone treatments (not all of which are completely ethical, especially if not disclosed at the time of purchase) led to diffusion treatments of many sapphires (along with some other gem materials). Diffusion treatments are a process in which other elements are either intentionally or accidentally forced into the stone through extended heat treatments. The problem with many of these stones is that the treatment leads to a change in color that is often only on the surface. If it becomes necessary to repolish the stone for some reason, the color underneath is completely different.

If only the very wealthiest people were interested in gemstones, than it wouldn't be necessary to treat many of these gem materials. But we're living in an egalitarian society now and everyone feels they should have the right to own a beautiful stone (fortunately, since I wouldn't be in business if that wasn't the case). There is far more demand than there is supply for the finest examples of some gem materials, hence the need for treatments to enhance the natural beauty of the gemstones coming out of the earth.

My next posting will discuss sapphire treatments.

Pictured above: Natural color fine cornflower blue sapphire.

Two days ago a young couple came into my store with a set of two bands they had bought at a local gallery/shop as an engagement ring set for her that they wanted sized. One of them held a large, extremely low quality rose cut diamond (this is an old style of cutting in which the bottom is flat and facets are cut in a dome like shape on the top---but while the cutting style was old, these were modern cuts) in a low bezel setting that was attached to a very thin plain, hammered band (too thin, in my opinion, for a stone of that size). The stone was so heavily included that it was not transparent at all. The current "rage" in "designer" jewelry is to use rough diamond crystals or similar odd cuts of low quality diamonds. It keeps the designer's costs down but they can still say it's a big diamond (or at least that it is a diamond). A lot of these goods would have been used as industrial stones a few years ago, but these days everyone seems to be trying to shave their costs. Frankly I used some diamond crystals in my jewelry about 25 years ago, but I tend to be a little ahead of the times I guess.



The second ring (meant to be worn with the first) was the same design but with a much smaller rose cut stone that the customers were told was a grey diamond as well.





One of the first thing I asked this couple was if they had recently purchased the rings, and when they said they had, why they weren't having the store they bought the rings in size the bands.
After all, I always include free sizing (anytime) whenever I sell a piece of jewelry, and frankly I think that any store that sells rings (excluding perhaps antique stores) should offer the service. If you pay a lot of money (and this couple did) the rings should be made to fit. If I did the sizing I was going to charge them and that seems kind of silly to me. They said the "designer" who made the bands was in California, but I told them that the store that sold them should at least have a local jeweler they worked with who could do it for them. They decided that they would go back to where they purchased the rings and ask them to do it.



However, that isn't what this is really about. Because I am a Graduate Gemologist, and because I am always thorough when looking at a piece of jewelry someone presents me, I took a closer look at the stones. When I looked at the smaller one, I realized I could see a streak of blue in the stone. Now ANY diamond crystal that shows blue in it would be properly cut (into a modern brilliant) and sold as a blue diamond, even if the color doesn't extend through the stone. As a matter of fact, most natural color blue diamonds that I've been shown by dealers, are stones that you have to hold up and kind of look in the corners to find the blue in them. Obviously there are blue diamonds that aren't like this (I've sold one and the Hope Diamond is a most notable one), but the bulk of them are, as blue is such an incredibly rare color in diamonds.



My suspicions now aroused, I checked the stone with my diamond tester first, and when the reading came back negative, took a closer look at the stone under the microscope. Sure enough, there was a blue streak as I might see in a very low quality sapphire and there were inclusions indicative of it being a sapphire. We then had a longer discussion about what the salespeople had told them about the identity of the smaller stone and they insisted they had been told it was a diamond. At that point I told them that they had to go back to the store and deal with that issue first as it was far more important than the sizing issues.



Legally, if they were told in writing (definitively) or even verbally (harder to prove), that the stone was a diamond than that is what they are entitled to have and it is the legal responsibility of the store to provide them with the same ring with a diamond in it. Ethically it is also the RIGHT thing to do.

Most customers, when they are buying a piece of jewelry are buying blind. They have no real idea of what they are getting and it is up to the jewelry store to make sure that they are clearly told exactly what it is. I haven't heard back from this couple about what happened (not sure if I will either, as the bearer of bad news is often not appreciated much) so I'm not sure if I can provide readers with a final comment on this.



However, my point in this posting is that all jewelers (or stores selling jewelry) have both a legal and ethical responsibility to fully disclose exactly what a customer is buying, and if the customer does not understand the information, they should explain it more thoroughly. As a customer, you should always make sure you shop at jewelry stores where full disclosure is a normal part of the sale, and you should also insist that any information relating to the identity, or quality, of a stone is clearly written on the receipt.



Next posting: Gemstone treatments

Pictured above: One of my favorite pins: 18k, 22k gold with Tibetan turquoise, Chinese freshwater pearl, fancy colored sapphires, and diamond.

I always enjoy selling new designs more than old ones. Don't get me wrong. I always enjoy selling any of my jewelry. But, when I have a new idea, and it sells almost right away, or fairly soon after I make it, it gives me a much better kick. It means to me that I wasn't just imagining things when I decided it was a great piece to make.

While I also enjoy selling to anyone who comes in my shop, it's always nice when the "special" pieces go to someone I know a bit, who I know will appreciate it more. The drusy chrysocola pendant purchased in my first went to a somewhat older (as in age--she's 86) customer of mine, who's son and daughter-in-law buys from me quite regularly as well. She's a great person, travels extensively and, most importantly, has a wonderful sense of humor. And she loves my jewelry. What more could I ask?

I had put the piece in my window display and she happened to notice it as she walked by. No real selling involved here. Once she saw it, she just knew she had to have it. I wish it was this easy all the time!!!

In my next posting I'm going to get into some ethics issues revolving around the jewelry business as it seems to have come up a few times in the last few days.

Designing a piece of jewelry is different for every jeweler. Some people are good sketch artists and can visualize and draw up ideas beforehand. Some people are good with the computer and can use Cad/Cam programs to build designs with that. Personally I just like to get in there and muck around with the metal. Sometimes I'll do a rough scribble of what I would like to do (I particularly like to do this on the walls of my workshop) but usually I just like to go to work. The gemstone I'm working around, and the metal I'm working with, often dictate where my designs will end up. Factors like durability, wearability and cost also enter the picture, especially when I'm working with large stones.





Every once in awhile I have an ah ha moment. For some reason it's almost always when I'm in bed (often asleep--hence the bags under my eyes all the time). One of the dominant themes that runs through a lot of my work came to me that way over 20 years ago when I was trying to do a new piece for my wife, Kathy, with a mobe pearl and some diamonds she had gotten in a piece before she knew me.


I had the same thing happen with the drusy chrysocola pictured in my first post (although it wasn't quite so meaningful). I woke up with the concept that I wanted to make it fit into a basket of sorts and that I wanted to cover up and use the brown part of the stone as the base for the design element while allowing the drusy part of the stone to speak for itself. The basket idea worked from an economic standpoint as well as I didn't have to build a large heavy bezel and back for a rather large stone.


Creating the actual piece, of course, was not nearly as simple as I anticipated at first, especially once I decided to add the diamonds. Soldering pieces onto an open wire basket without the whole thing falling apart is always fun. Trying to set stones into bezels (the piece that holds the stones) when there is no real support (I had to do it before I set the chrysocola) is also a lot of fun. Since I still handcraft so much of my jewelry, a lot of the things that I do are still a bit tricky, but a little challenge is always far more interesting than doing the same thing over and over again. And, as it happens, I made something up that I really liked.

In my next post I'll talk about actually selling the piece.

Buying gemstones

One of the best things I get to do in my job is buy gemstones. First of all it's a great way to spend money and not feel guilty about it! Over the years I've developed a more limited number of suppliers who can supply the quality of goods that I need along with offering products that meet my ethical needs (proper disclosure, sourcing, etc.). Most of them have become friends over the years and we all recognize how codependent we are. If they offer me a great product at a fair price, I can sell more of their product.


It's always fun to sort through hundreds, or even thousands, of loose gemstones to find that one or two that just moves or inspires you, or you know is simply so beautiful, that someone will come along who loves it as much as you do. I have different sources for different types of goods; some I only buy one or two types of things from, usually because they're specializing in a particular product, but some carry a range of goods that I buy. My primary sapphire dealer also carries beautiful tourmalines, garnets, peridots, etc. but doesn't sell pearls or opals. My opal/pearl supplier doesn't carry anything other than that.





My latest purchase was from Penny who's a West Coast based dealer who carries a lot of cabochon gemstones and a wide mix of goods. She always has some interesting pieces, more funky than my traditional stone suppliers, and while I don't buy a lot of goods from her I can always find something that excites me. The drusy chrysocola pictured in my previous posting (7/17) came from her in my latest purchase. The stones pictured with today's posting also came from her.


In my next posting I'll talk about how the design came about for the drusy chrysocola.




Pictured: Rutilated quartz, carved onyx, Argentine agate

I'm starting my first blog.

I'm starting my first blog today, July 17, 2009. This is my latest piece for the cases that I made up about two weeks ago. It sold yesterday to one of my favorite customers. Tomorrow I'm going to tell you how I got the stone for this piece and how I came up with the design.