Monday, September 26, 2011

Two for One? Turquoise Doublets

Remember this turquoise?


It has a little secret:  it's a doublet.

A what, you say?  Never heard of it?

A doublet is a combination of a precious or semi-precious stone and another, lesser material (such as rubber or glass) glued together. It doesn't happen naturally but is man-made, for any one or more of the following reasons:

- The gem material is too fragile / too expensive alone. This happens often with opals. The fragile opal often material needs a backing for stability before it can be set in metal.

- Alternatively, opals (for example - doublets do happen with other stones but opals are one of the most common examples) can be very expensive. Using less of the pricey gem material and more of a low-cost backing can help defray the end cost of the jewelry. And since, once set, the backs of most stones are not seen, a doublet usually doesn't detract from the finished item.

- To enhance the stone. Again, this happens fairly often with opals. Depending on the type of backing, an opal can become even more vibrant if it is doublet-ed.

Here's an example of an opal doublet (viewed from the side of the stone)
:




Getting back to my turquoise stones, I don't actually know *why* the turquoise was doublet-ed; but that's how it came to me. And for the ring setting, it didn't matter because no one would ever see the back. But it certainly can make a difference in other situations. For example:


source: Contrariwise Blog

This is not my own work, but that of another 'smith. I am using her photo to illustrate how sometimes you may want an open-back setting for your stone pendant - in this case it let in more light - and also can be a nice decorative feature. A doublet will *usually* not work for something like that. Here's why:


It's a style of stone-wrapping I used to do, years ago. With another piece of turquoise my Dad gave me.
Perfectly nice from the front, eh? But look at this:


Uh-huh. Not so pretty now. The back of this stone, just like the one in the bezel set ring, is doublet-ed. With what I can only guess is some sort of plastic. Why? I have no idea. Maybe the back wasn't polished, was rough, and that wouldn't have felt comfortable wearing in a piece of jewelry. Nor would it have been easy to bezel set with a lumpy and bumpy back. But I didn't know how to stone-set then. This piece was made for me, so I didn't worry about the back, but I would have never bought anything like this to sell to someone else, unless I could have covered the back up.

Doublets are a perfectly acceptable item to use in jewelry, as long as they are disclosed and they are used in an appropriate manner. But it wouldn't hurt to look as closely at the back of your jewelry purchases as you do at the front. A finished piece of jewelry should be just as well-finished on BOTH sides.   :)


Tuesday, September 20, 2011

American Picture Jaspers: Biggs, Deschutes and Bruneau

The term "picture jasper" encompasses a wide range of stones. Jasper in general is found all over the world, but American picture jaspers are a broad part of this spectrum.

Most picture jaspers in the U.S. come from Idaho or Oregon. Oregon in particular has produced some stunning jaspers. While stones are often named for the person who found them (for example, Pietersite is named after Sid Pieters, the man who discovered it), most jasper names indicate their location. Biggs jasper is from Biggs, Oregon. Bruneau jasper comes from Bruneau Canyon, Idaho. And so on. Each jasper is distinctive and (for the most part) easily identifiable.

Biggs and Deschutes jaspers come from a very similar area of Oregon, and sometimes it's hard to tell them apart. Both are relatively rare in today's market as, depending on what you hear, the mines(s) are either "played out" (e.g. not producing any more), or inaccesible due to being paved over by a highway...what I can tell you for sure is that when I do run across either of these jaspers for sale, which isn't all that often, they are a good bit more expensive than most other jaspers I buy. But buy them I do, as I can afford to, because they are truly lovely stones.

Here's the first money shot:


A nice Biggs oval with some good color variation. I've shot it vertically but am thinking of setting it horizontally, like this.  Here's the side view:

This is a more "true" shot of the coloring. The edges are pretty good, though a little uneven, and it's a fairly thin cab, which of course also plays into the cost factor. The bigger and thicker the stone, the more it costs, of course. Here's a great example:


Here's another Biggs cab. LOOK at how thick this is! And it's a more unusual cut. The colors are good, as you'll see in the next shot:


Oh yeah. This is what I would consider a "specialty" cab. It's pretty large, it's an unusual cut, and the coloration is GREAT. And no, it was not in-expensive. But I can't wait to build some big, beautiful design around it.  :)

Funny how neither of those look like the first Biggs I posted, eh? I believe that's because the first one might be considered a "Biggs blue", which is an even less plentiful version of the Biggs jasper.

On to the Deschutes:


Talk about some kind of beautiful stone...another "specialty" but it is just so lovely. And it's also thick:


There's going to be a lot of metal invested in this gorgeous rock.

Last but not least, a horizontal shot (which may be how I set this one, too):

So now you're a little more familiar with some of the predominant Oregon jaspers.  Last but not least, Idaho!

Idaho's best-known stone is the Bruneau jasper, from Bruneau Canyon in south-central Idaho. It comes in a variety of colors, but is mostly known as pale brown and cream. I would say it is always "soft" colored - at least the Bruneau I've seen. It's more pastel-hued than popping with some of the rich colors found in other stones, but the soft beauty is what makes it gorgeous. See for yourself:


This is the only piece of Bruneau that I own. As usual, the darkish spot toward the bottom of the stone is from the camera. When I bought this stone, it was the first time I'd seen Bruneau Jasper. I knew nothing about it (fortunately the seller was also the stonecutter and he made sure I was informed). It was a bit costly even back in the day - I've had this stone for several years -  and it's a really great example of the soft lines and colors typical of this stone. EXCEPT for that pink at the top...it's not real. The camera read it as pink when it's a mid-colored brown. The more accurate colors are shown below, in the side view:



The sides are absolutely flat and even, and the stone is cut BEAUTIFULLY. The man I bought this from lives in Arizona and he cuts some gorgeous, gorgeous cabs.

Now you're a little more educated about some American gems. Stay tuned to for future posts once these are set and finished!  :)

Wednesday, September 14, 2011

The Swedish Blue Has a Secret

You know I am always happy to share fascinating facts about gems. And this one is rather grand.

Let me get right to the photo for once, of a little something called Swedish Blue.


The dark blue blob on the bottom part of the stone is from the camera, but I think you can see the overall fabulous color of this cabochon.

And this one, which is even more gorgeous:


So we agree, yes? They're lovely. But what are they? Well, I'll tell you what they're not:  a gem. Or a mineral. They're not glass, either, though they do look a bit glass-like in person. They're called Swedish Blue, and they are...drumroll...slag. Yeah, that's right : iron ore slag.

Slag is the byproduct of smelting metal ores. Essentially these are the "impurities" that were removed from metals like copper, aluminum, and iron. Over time, this slag (which was typically just dumped as waste) changed into a glasslike substance. These particular cabs are called Swedish Blue because they come from a small town in Sweden where the slag was dumped in the 16th and 17th centuries. Fascinating, no?

These babies are OLD! And  so unusual! And a little bit rare, since they only come from one place in the world.

I love the thought of something once considered to be waste now being reclaimed as an item of beauty. I can't wait to sit down and design around them!  :) 

Friday, September 2, 2011

Natural Wonders: Charoite

The lavender hues of charoite are like nothing I've ever seen. Found only in Siberia (Russia), the stone is named for the Charo river. It is a stone so clearly unlike any other known in the market that it can pretty readily be identified by sight. Even a novice, having once seen it, is unlikely to to confuse it with anything else.

The gem has what is often described as a  "pearly" luster. Its coloration is typically what I would call "soft", meaning that it's pastel-y and also a bit muted, unlike the "'hard" bold colors of chrysocolla, for example, with some swirls showing through the stone surface. Discovered in the 1940's, it was not widely known to the rest of the world until thirty years later. It's "said to be opaque and unattractive in the field, a fact that may have contributed to its late recognition" (so says Wikipedia, so take that with a grain of salt). I've never seen it "raw", so to speak, but I can tell you that when it is cut and polished, it is very much the opposite of ugly.  :)

Here's some photographic evidence:


and - my usual disclaimer - the photo cannot show you the real beauty of this stone. It looks a bit "flat" in the picture, but it definitely has that lustrous look in person. The colors are pretty true. ranging from lavender to a deeper purple with a tinge of brown and black mixed in.

It's a fairly soft stone, so best used in necklaces and earrings, rather than rings or bracelets. I think the stone above would make a perfect pendant, with the point hanging down as photographed.

 One more example:


Is it expensive? It's hard to say. The stones pictured above were relatively INexpensive, but I've seen some online for quite a bit...although I don't buy stones on line because I always believe I can find a better value at the gem shows. I bought my stones a few years ago so the price may have increased since then, especially as it's only found in one location worldwide.

Purple tends to be a divisive color - people either love or hate it. I personally love it! And this lavender hue is really unusual.

What do you think? Love or hate it? Indifferent? I'd love to know!