Heart of Stone Studio Blog

The Scoop on Adobe Lightroom

I have designed and built my 75-page website, Heart of Stone Studio.com, all by myself. Every week, I post an average of fifty new gemstones to the site that are purchased by jewelry artists and collectors. Until recently, I was doing all the photography myself, which included editing of photos of stones to make sure that the depiction of each stone, especially color, was accurate.

I had thought that Photoshop was the ultimate photo editing program, until I saw Adobe Lightroom on my friend Doug Von Gausig's computer. Doug is a professional photographer (and also mayor of our neighboring town of Clarkdale, AZ), who takes thousands of photos every week and uses Lightroom to organize and edit them.  When he showed me what Lightroom could do, I was immediately hooked. I went out and bought the program,then took a workshop to begin to better understand how to use it. 

The Lightroom working screen is a very sexy black that you can make even more attractive by adding your own personalized logo and company name. Photographers do this because Lightroom is not just a behind-the-scenes type of program; it also can be used create and show very slick slide presentations, with music even, to clients. You can also use Lightroom to set up your photos on a web page. And of course, it's also helpful in preparing to print photos. So it's a real start-to-finish type of program.

But I'm getting ahead of myself. If you've read my previous posts about Adobe Bridge, you'll have an idea of what Lightroom can do because it does all of the things that Bridge does, except that photos have to be imported into Lightroom before you can work with them. (And, Lightroom is an independent program that you have to purchase separately.)

Like Bridge, Lightroom has a main work area with a "filmstrip" of smaller images running across the bottom, showing you everything that you have in a folder. Lightroom is different in that it has two main working modes: "Library" and "Develop."  The Library mode is where you do the main importing, organizing, and exporting, although it also has some quick editing features.

But it's the Develop mode that's really neat: Switch to "Develop," and Lightroom presents you with the same main viewing area, only now you get an expandable column on your right. This is where you can easily access and adjust all the main aspects of a photo--tint, temperature, exposure, white balance, color, brightness, contrast, saturation, clarity, etc.--just by scrolling up and down and using your mouse to move a point along each slider (scale). You can even select individual colors and instantly adjust them to your liking.

Like Photoshop, Lightroom has a tone curve, that infamous graph with the diagonal line across it. In my opinion, Lightroom's tone curve is more user-friendly--Once you've got it open, you can click and hold on any area of the photo and, using your mouse, "slide" the cursor up or down right on the image to lighten or darken all the tones matching that of the area you've selected. If you want to fine-tune your changes, you can then go over to the sliders in the right column and adjust them individually. You can adjust color and contrast in the same way. In Lightroom 2, you can even replace a washed-out sky using a graduated filter that is easily adjustable. The only thing you can't do is outline (isolate) and select an area of an image to change--That you would have to do in Photoshop. And, as mentioned before, Lightroom doesn't do layers.

But as I don't work often with layers, I'm enchanted with Lightroom. What's really neat is that Lightroom enables you to set up your "before" and "after" images in a split screen so you can compare what you've changed with the original. The left (history) column on the screen keeps track of every change you make, so if you don't like it, you can click on an earlier step to undo a certain change.

The thing I like best about Lightroom is that it allows you to make changes to multiple images at once. You can do this two ways. One is by the Copy and Paste buttons: Say you have a dozen photos that you shot indoors, all of which need to be lightened and have their white balance corrected so that they're not all greenish from the overhead flourescent lighting. You can select one representative photo, correct the white balance with a single click, make your other adjustments, then hit the "Copy" button, which makes a complete copy of your changes. You can then select one, some or all of the other photos and hit the "Paste" button, and they'll all instantly be adjusted exactly the same way.

Another way to do this is to pre-select all the similar problem photos by highlighting them, make your changes on one photo, then click the "Sync" button, and all will be immediately synchronized and adjusted the same way. Can you imagine how this will speed up your work flow? It's fabulous!

The main thing that makes Lightroom responsive and just plain fast is that, believe it or not, even though you've imported your photos into Lightroom, it's not your actual photos that you see on the Lightroom screen. They're not really sitting backstage in the program. They're virtual! And all the editing changes you make in Lightroom, well, they're virtual, too. They're just a set of instructions that Lightroom saves and assigns to that particular photo file. This is so cool because it means that even though you have tons of photos copied into Lightroom, because they're only data files, not real photos, they take up hardly any room on your computer.

That means that, despite what you do inside Lightroom, your original photos--be they jpegs, tiffs, or even Raw images--are sitting untouched in another folder on your computer. The virtual changes that you make in Lightroom become real when you go back to the "Library" mode and hit "Export." Then you're presented with dialogue boxes that allow you to save your changed virtual photos as real .jpg, .tiff, or .xmp files for Camera Raw photos, and you can assign them new file names if you want, or over-write and change your existing jpg and tiff photo files. So when you're done with the Export, you can close out Lightroom and go to your target folder and there are your photos, all cleaned up, corrected, and perfect.

The capabilities I've mentioned here are just the tip of the iceberg in terms of what Lightroom can do. Again, this program is not for someone who just wants to print quick pix for the family photo album. But it is a wonderful new tool for those of us who have lots of photos to review and adjust. If it's something you're interested in, I suggest dropping by Adobe.com, where you can sign up for a free 30-day trial download.

 

Adobe Bridge: An introduction

     Adobe Bridge and Adobe Lightroom are, at their roots, sorting programs. They allow you to review lots of photos at once and organize them. But they also do so much more. You can use either program to edit your photos, and if you hit Control-R (Command-R in Macs) while you're in Bridge, it will take you to a special page where you can quickly edit Camera Raw photos and save them any way you want, in any folder you want.

     In fact, these programs seem so similar that I asked our workshop teacher, Markus Pfitzner, why we had to learn both. Here's essentially what he explained: Adobe Bridge allows you to quickly access any photo file without having to go through the extra step of importing it. Just select the folder you want to see, and Bridge opens all the photos in it for you. Plus, you can do most of your photo editing right in Bridge, although it can't do selections, masks, and layers like Photoshop does.

  Bridge is linked with Adobe Photoshop, which means that it's automatically installed when you install Photoshop onto your computer. That also means that a double click on a photo displayed in Bridge will open that image in Photoshop, and conversely, when you're already in Photoshop, hitting Control+Alt+O (Browse) will open Bridge.

    You can set up Bridge to label each photo and add copyright information to it (which is crucial if you're sending it out into the world), plus, you can add keywords. Keywords are little descriptive tags that you type in about that photo. For example, I have some of the flower shots that I took at the Mendocino Coast Botanical Gardens on my Heart of Stone Studio website (to drop by and take a look at them, click here: Judy's Photos). The Dahlia photos I took could have been assigned keywords such as: dahlia, flower, garden, California, Mendocino, Botanical Gardens, etc.  Typing in keywords might seem like extra work to do just when you'd prefer to spend time admiring all your photos, but it's not so bad because Bridge and Lightroom will assign the same keywords instantly to a bunch of pictures if you select them ahead of time.

     And the absolutely coolest thing about keywords is that you can use them to search for and pull photos for you. Say you shot flowers like I did in Mendocino, but over the years you also shot them in Hawaii, Kew Gardens, Vermont and in your own backyard--but those photos are scattered around different folders on your computer. If you go to Bridge and do a keyword search and type in "flower", Bridge will rummage through all your files and pull up every photo of a flower that you've ever taken, assuming that you had entered in "flower" as a keyword for each of them. Isn't that neat?

    In addtion to organizing, labeling, and basic editing, Bridge also enables you to crop and size your photo before saving it, and gives you options which enable you to save a copy for your files and a smaller copy for e-mailing or posting to the Web. And it does all of this while hovering over your photo files like an alien spaceship, grabbing a hapless file here and there (at your command), making changes, and plopping it back wherever you direct. It's quick and easy.

    So, you say, if Bridge is this great and it comes free with Photoshop, then why should I consider investing in another program like Lightroom? "Ah," I answer, "there are lots of reasons, the main one being that Lightroom does everything Bridge does, but also does so much more..."

   And I'll discuss Lightroom in my next post.

What is Camera Raw and why do I care?

     The workshop I attended in Mendocino last weekend was based on Camera Raw. You might have heard this term bandied about...What exactly does it mean? Basically, it refers to an image that is taken using every part of a camera's sensor and not altered or edited in any way by the camera or its programming. You might have thought you're already doing that when you take a picture, but no, not when you're taking the usual JPEG photos.(You'll know you've taken a JPEG when you load your images onto your computer and each photo will have a file number followed by the following tag: ".jpg")

    JPEGS (pronounced Jay'-pegs) are the product of an editing program approved by a group of professional photographers and photo editors. What JPEGs do is edit an image down to a manageable file size so that it doesn't take up too much room on your memory card or computer. The editing is, simply put, automatic, based on a set of rules that reduce detail by grouping similarly-colored pixels together. For example, if you have a little area in your photo with two yellows that are very close in color, JPEG will go ahead and combine those into just one color yellow, thereby halving the amount of information coding needed in that area. Most of the time, this automatic editing is not especially noticeable, although there is one major drawback: Each time you save a JPEG on your computer, you apply the automatic editing program once again, and so that means that with each save, you lose information. That means that over multiple saves, edges within the image soften, the focus is not quite as crisp, and details are modified or even lost.

    Some photographers don't like that loss of information. If anything is going to be cut out or modified in their photos, they want to do it themselves, and be in control. That's where Camera Raw comes in. Camera Raw photos are exactly everything the camera saw when you pointed the lens and pushed the shutter button. The majority of family cameras are not equipped to shoot Camera Raw; only the fancier models do. (If you're in doubt, check out your user's handbook). Camera Raw photos have no editing, no compression, and no alterations beyond the aperture opening, shutter speed, and related settings that the photographer set the camera at.

   Now, if you're following what I've been saying, your next observation will be: "Well, with no editing and no compression, that means that the file size of each photo will be a lot larger than usual, right?" and you'll be absolutely correct: Camera Raw files are humongous. Fortunately, gigundo memory cards are coming down in price, as is the cost of additional memory for your hard drive, or even for external hard drives. And to serious photographers, it's worth it.

   This weekend was the first time I shot in Camera Raw, and to give you an idea of how much space Camera Raw takes up, I shot 262 photos and I still hadn't filled a 4Gig memory card. So the Raw photos aren't impossibly big.

But let me tell you some other things I learned about Camera Raw:

1. Camera Raw photos can NEVER be changed. Sure, you can delete them, but you can't alter their content. Well then, how do you edit them, you ask? Well, you need a professional-level photo editing program, such as Photoshop CS3, or Lightroom 2.

Here's how it works: You import a Camera Raw photo into one of those Photoshop programs, and as you edit it,  the program can be set up to save your editorial changes to what's called a "sidecar file," a little file with an ".xmp" tag that gets hooked onto the Raw file and travels around with it (on your sayso). When you open the Raw file, its sidecar .xmp file kicks in and applies your editorial changes, which you then see on your computer screen. Better yet, these programs also give you the option to either save your edited image as a JPEG or a TIFF (uncompressed) file, both of which can be easily read by your and other people's computers. But even with your new, edited JPEG, you'll still have that unchanged Raw photo stored on your computer. Or better yet, you can set up an external hard drive and store all your Raw images on that, like a museum archive.

2. This whole idea of storing unchanged Raw photos in an archive can be really appealing, except that there's one catch: The particular Camera Raw format you use is tied into the particular model of camera you're using, and five or ten years from now, especially if your camera model is discontinued, new versions of photo editing software may no longer recognize your camera's Raw images and you won't be able to open or edit them using the new software.

How do you get around this? One way is to set up your camera to take a Raw image and a JPEG image simultaneously. No extra clicks of the shutter; it's all done automatically--more professional cameras can be set to it easily, just look under your "Quality" topic on your camera's menu. You can edit either image, but save a master copy of your JPEG untouched as your long-term archive photo, because those will always be accessible.

Or, here's another idea: You can import your Raw images into Lightroom with the special instruction that copies them and converts them to digital negatives, or DNG format. The DNG format is very similar to Raw, except that it is considered "open source," which means that any program will be able to open it, now or later in the future. Once in the DNG format, your images can easily be edited and saved.

3. One last thing that I learned the hard way: Microsoft Windows won't be able to "see" your photos. In other words, they won't open up as photos in Windows Media Player or any of its other photo organizers. That's because your computer just sees your Raw images as batches of data; there's nothing to translate them into color pictures for you. So don't get crazy (like I did) when you can't see your Raw photos on your computer--You'll have to import them into a program like Photoshop CS3, Adobe Bridge CS3, or Lightroom 2, and then you'll be able to see and work with them.

That's the scoop on Camera Raw. Next, my take on Bridge and Lightroom.

   

About Adobe photo editing programs: The pros and cons of Photoshop

   I've recently returned from a photo-editing workshop at the Mendicino Art Center. Taught by Photoshop specialist and educator Markus Pfitzner, the workshop dealt with photographing pictures using the Camera Raw format, then importing, organizing, and editing them using two Adobe programs: Adobe Bridge and Adobe Lightroom. I want to discuss the neat things I learned at this workshop.

    But first, I want to point out that the major photo editing program in use today is Adobe Photoshop. CS3 is the most recent version, and is by far the most powerful. You can buy a beginner's version of Photoshop, called Elements, for not much money at big box stores, but if you can at all afford it, I suggest making the investment in CS3. Even buying the previous version, CS2, online at websites like eBay would be a better investment than buying the much more limited Elements. I know of people who have a family member who is a faculty member or student and ask them to buy the educational version of CS3--It's essentially the same as the professional version, but at a fraction of the price.

   Photoshop is an incredibly impressive, amazing piece of software. You can edit photos with it, add type, and even convert your photographs to artworks because you can add texture, use brushes, layer and mask images--It's all there. Having sung Photoshop's praises, I will add that it is not a user-friendly program. I have often said that someone could get a Ph.D. just in Photoshop, and still not know everything there is to know about this program. So if you just want to crop and size photos for your family album, skip Photoshop and stick with the software that came with your camera. But if you are serious about your photography and want to really master digital photo editing, Photoshop is the way to go.

   Once you get the program, load it onto your computer, and open it up, it's pretty bewildering. Plus, what you see on your screen is just the tip of the iceberg. That's why I suggest you hunt down as many video tutorials as you can: Search your local library; check out eBay; borrow from friends, etc. Even one good tutorial on a CD will get you started moving your mouse around the space and getting an idea of which button does what.  After tutorials, check out books on Photoshop. Starting with the books was, for me, pretty overwhelming. Plus, I was impatient and just wanted to "get to it." That's why I suggest getting your feet wet by following a step-by-step video.

  All I ask is that you stick with it for several months. During that time, if you've given Adobe permission to send you information, you'll probably receive e-mail invitations to lecture and workshops. If the topic appeals and you can afford the time and registration cost, try one out. But be forewarned: The official Photoshop workshops offered in big cities like Phoenix routinely have 500 or more people attending, so you won't be getting any individualized attention. A better place for that is your local community college, university, or art center. By signing up for that level of workshop, you get the opportunity to have a Photoshop expert in the same room with you to answer your questions--which is worth its weight in gold.

    But once you've mastered the basics of Photoshop, you'll never want to use anything else. You'll see why it's the preferred choice of photographers, artists, illustrators, and web people.

    Next, spotlight on Camera Raw, Adobe Bridge, and Lightroom.

   

A Review of the Denver Gem and Mineral Show

   The end of summer has been really busy for me, and Fall got off to a good start with my trip to the Denver Gem and Mineral Show, where I was buying stones for my website, www.heartofstonestudio.com. Every time I mention this show, which is held annually in mid-September, people ask how it compares to the Tucson show, and is it worth going to? This is my second year going, and I'd like to share my thoughts with you about it.

   The Denver show can't really compare with the February Tucson show--it's a fraction of the size, held in six or seven venues instead of Tucson's dozens. Having said that, I think that it still has merit. I'm finding that several of my suppliers now make it a point to set up in Denver as well as Tucson, so it's a worthwhile trip for me to visit them and stock up mid-year between Tucson shows.

   Let me tell you a little bit about the shows. Five of the six venues are within a mile of one another, and all of these are located in an industrialized area just north of the junction of interstates 70 and 25, which is about ten miles north of downtown Denver. Two of the shows are at hotels--the Holiday Inn and Best Western (although the sign at the top of the hotel says Quality Inn) which are within walking distance of each other. These two shows feature minerals rather than gemstones or finished jewelry, although a small percentage of those are available. Here, international dealers rent rooms and fill them with spectacular (and pricey) collectible mineral specimens. Some rough material is also obtainable. These shows are the first to open during that week. I suggest that if you're driving, you get there either a half-hour before the 10am opening time, or after 4pm, because the parking situation is horrific. These shows don't require any registration, and as far as I know, they are open to the public. Dealers will sell at retail prices, but will usually give wholesale discounts to qualified buyers who bring evidence of their resale tax status.

   Three other shows are ten blocks away at the Denver Merchandise Mart. The Mart is a huge complex, and unless you know where you're going, the shows are somewhat difficult to find. The upside is that parking is relatively plentiful.

   Toward the rear on the west side of the Mart complex is the Pavilion building, the site of the International Gem Show. This wholesale show starts a couple of days after the mineral shows, and the noontime opening was crowded and disorganized this year. The show is a mix of mostly finished jewelry, some cabochons, a few dealers in faceted gems, and some Asian dealers selling bead strands. It's not a huge show, but it does have a decent variety.

   The day after the Gem show starts, the Fossil Show opens at the Mart's Plaza area, which is on the opposite (east) side of the complex. This was the first year I attended the Fossil Show, and I was just blown away by it. Tucson has fossil venues, but to me they seemed more spread out and haphazard, whereas Denver's Fossil Show appeared large, well-organized, and in an attractive setting. Interspersed among the booths were full fossil skeletons of a 12-foot tall cave bear, a baby tricerotops, and several others. You could find 3-D trilobites complete with waving antennae, ammonites the size of hubcaps, bug-filled amber, and hundreds of fossil fish, including one whose bony head was turned as if to swim out of the limestone background. It was more fun than a museum, because you could buy the specimens if you wanted to.

   As I entered the fossil show, which is open to the public, I was dismayed to see a dozen schoolbuses disgorging hundreds of grade-school kids, but the show was so large they really didn't make viewing difficult. What's more, it was neat to see a 15-foot-long duck-billed dino skeleton walking among the crowds, bony tail waving above everyone's heads--It was a clever reproduction made by a dinosaur educator who straps himself into a harness inside the pelvis and literally makes the creature "come alive" to schoolchildren. If you and/or your kids are fossil aficianados and can get to Denver during this time of year, the fossil show is highly recommended. Plus, interspersed among the fossils were booths with slabs, cabs, carved stone boxes, mineral sculptures and art pieces. This was a very big, and very good show.

   Across the street from the Mart was a small miner's show that specialized in cut slabs and rough material. There were two other shows that I didn't have time to attend. One was the weekend Gem and Mineral show which was open to the public. Another was a bead show in a venue close to the airport. But that was pretty much it.

    In all, I would consider Denver a smaller but representative taste of Tucson. Plus, it is more manageable than the crowds, crammed hotels, and general insanity of the Tucson show. If you want to try the Denver shows next year and you're not planning to spend much time downtown, I would recommend staying to the north of the venues, preferably in or near the suburb of Westminster, which is literally a ten-minute drive (traffic permitting) from the venues and about 40 minutes from the airport. Motel accomodations are also available a few miles outside the Denver airport, but the drive in to the venues is longer. Parking is easiest at the Merchandise Mart, and a shuttle is available from there to the other locations.

   

 

   

   

The importance of cut in faceted stones

      Both diamonds and colored stones have something in common, and that's the importance of cut. An excellently-cut stone can dazzle the eye with light and sparkle, and distract from weaknesses such as inclusions and less-than-ideal color. Conversely, a poorly-cut stone is a sad thing, as though the material couldn’t live up to its potential.

     When I first began shopping for faceted stones, I really tried to carefully look at what I was purchasing. But it's hard: Try standing in front of a dealer's booth filled with gems, the halogen lights beating down on you, other shoppers jostling you and trying to get waited on, and you will soon realize that you have to make quick decisions on the quality of a stone. I made some mistakes and learned pretty quickly, and honed my skills by looking at hundreds, even thousands of faceted stones.

    What I came away with was the impression of how much drek there is out there, yet people keep buying it. I am especially disheartened by how bad much of the cutting is, especially with smaller stones. You would think that it's relatively simple, once you've learned how to cut a gemstone, to do it consistently and symmetrically, leaving out the bad inclusions and working to bring out the beauty of the material. Nope.

     One confounding problem is weight. Diamonds and colored stones are sold by weight, not by size or shape. A hundredth of a carat left on a stone may not seem like much, but multiplied by thousands, even tens of thousands of stones, that weight can add up to big additional profits. The problem is, that added weight has to go somewhere, and it might go into making the stone deeper than it should be for an ideal cut, or its girdle thicker, or the crown (top) higher or broader. Working to include that extra weight results a slight but definite change in the proportions of the stone, which in turn affects how light enters and bounces around before leaving to greet the viewer's eye.

     Another problem is perceived value. There is pressure to squeeze the last iota out of a piece of gem rough, because this is not material that anyone likes to waste. Regularly “editing out” and tossing material with inclusions and other imperfections would drastically reduce the yield. However, sometimes the problems are so noticeable that a cutter can’t possibly include them, so he or she is forced to “work around” a serious flaw, which again might alter the proportions of the finished stone.

     The third thing to keep in mind is that not all gemstones are cut by experts. Yes, larger diamonds are, but some less-valuable diamonds and many, many smaller colored stones are cut by beginners. Do I hear a gasp? Well, they have to start somewhere. And unfortunately, many student efforts in gem-producing regions don’t end up on the rubbish heap. Most often, they are tucked into lots, which are larger quantities of stones made available to wholesale gem dealers. Back when I started as a jeweler, I purchased some lots of faceted stones, which seemed like great deals at the time. When I got them home, I found that 10-20% of each lot was composed of really fine gems, about half of them were OK—eye-clean, and the remaining 30 to 40% were what I would call trash—badly flawed and/or poorly cut. By the time I had sorted out only the good stones, my per-stone price had increased dramatically. I set the “trash” stones aside for students to use for practice, but some dealers will go ahead and put them into lower-priced jewelry.

     Now, I don’t want to give the impression that gem miners or cutters or dealers are unscrupulous people “out to get” the consumer. I prefer to look at it this way: Natural gemstones can be a crapshoot, from the minute someone gambles on locating a mine, to whether the inside of a piece of rough is as great as it seems on the outside, to whether a stone will hold together during faceting, through all the other risks and pitfalls involved with cutting, transporting, and marketing stones. This element of risk continues right on down to the consumer.

     Generally speaking, my sense is that the attitude among this world of gem dealers is: If you know what to look for, they can provide you with excellent gems. However, if you don’t know what you’re doing, they are not going to go out of their way to enlighten you. Never has the motto, “Let the buyer beware” applied so aptly as here.

     On my Heart of Stone Studio website, I do my utmost to present really top-quality cabochons, faceted gems, and drusies. If the stone is less than perfect, I disclose that right up front. Not every retailer will do that, but it has really proved worthwhile for me in return business because my customers know they can trust me. And that’s why I’m writing this blog, because I think we can all benefit from being better educated about gemstones. I’m learning all the time!

In my next post, I’ll try to explain how I evaluate the cut of a faceted stone.

More thoughts on PMC settings for stones

        PMC expert Bridgette Rallo has responded to my idea about using prefabricated faceted stone settings and incorporating them into a PMC design:

Prong bezels and bezel cups work well for a lot of different stones and can even be pushed a bit to fit stones that are close to the calibrated size. Be very careful with prong settings, though. Make sure that you have good contact between the stone and each prong. Dichroic glass is a wonderful alternative to a natural stone,

especially when it's an accent stone. Using a glass cab "dot" eliminates the need for two bezels. This saves a lot of space in your design. It is really worth it, after all is said and done, to learn how to make bezels for natural stones. There's a big learning curve but nothing comes close to a custom setting for a gorgeous freeform cabochon.

   

If any readers have had any experience with this, please write in and I'll add it to the discussion.

Restrictions on firing gemstones in PMC

     My previous posting with Rio Grande's chart on survivability of gemstones when exposed to the heat of a PMC firing has sparked a response from Bridgette Rallo of The Greenwoods Studio. Ms. Rallo is a jeweler, educator, Heart of Stone Studio professional customer, and expert on PMC. She says:

You know, Judy, I really question exactly how the stones they fired at Rio looked after they came out of the kiln...I have never heard of a stone that can survive a firing at the temperatures needed for PMC 3, never mind PMC+ or Standard. The only exception is calibrated hematite, which can take 1100 degrees for 30 minutes. I had an assistant who put a bezel into the kiln without removing a Mexican lace agate and I noticed it after about 5 minutes...the temp had reached 1030 degrees and I was able to salvage the stone but it did darken quite a bit. When Rio says the stone survived, they mean it didn't blow up in the kiln. But I will guarantee you that it had considerable color change. I get color change even on pieces of sea glass, which is why I make pre-fired bezels for them now.

    So, it appears that great care and discretion needs to be practiced when planning to include gemstones in any PMC firing. I am listing some other approaches worth considering:

--Firing only synthetic gemstones and CZs (Cubic Zirconias), although there is no absolute guarantee that these stones won’t change color or at least darken, in the kiln.

--Pressing the gem into plasticine to make a mold, then filling that mold with plaster of paris, popping it out when dry, and then substituting that for the gemstone during firing. After firing, carefully drill or chip out the plaster and you have an automatic seat for the stone. (I suggest drilling a hole through the bottom of the metal seat so that light gets into the stone from the back.) However, unless you’ve set up a bezel or other way to trap the stone in place, you’d have to glue it in, something that you wouldn’t want to do with an expensive stone because it is certain that it would eventually fall out.

--A third option that I’ve thought of but don’t know if it would work with PMC, is to purchase a pre-made prong setting (that fits the stone) and fire the bottom of it right into the clay of the piece, making sure that a bit of clay anchors the setting in permanently. Then you can set your gemstone safely into the setting after firing. Might be worth experimenting with...Any other comments or tips are welcome.

Next posting, my thoughts about the importance of cut in faceted gemstones…

Gemstone suitability for use in PMC

      Now that I have begun to offer melee diamonds and semi-precious colored gemstones on my website, Heart of Stone Studio, people have written to ask which gemstones can be used in firing precious metal clay. Genuine diamonds can, of course, and CZs (cubic zirconias) as well as synthetic stones, but real colored gemstones are another matter. For one thing, if the stone contains any major inclusions that heat and cool at a different rate than the surrounding stone, they can cause the stone to crack or explode. Or, a small fracture, when heated, can expand to become a big, damaging fracture. The other possibility is that the crystalline structure of the gem does not lend itself to firing. Regardless the reason, the result is a double mess--a damaged stone that's also locked in place in your piece.

     So, I called the folks at Rio Grande, a large and reputable jewelry supplier out of Albuquerque, NM. Their research department experimented with firing a variety of different stones in two types of PMC.  I've made up a chart of their findings that I hope the PMC enthusiasts will find useful:

Gem Suitability for Use in PMC	Information provided by Rio Grande
Gemstone	Dry Fire	PMC 3
Chrome Diopside	not available	Survived
Garnet: Almadine	Survived	Survived
Garnet: Pyrope	Survived	Survived
Garnet: Rhodalite	Survived	Survived
Garnet: Tsavorite	not available	Survived
Hematite	not available	Survived
Moonstone	Survived	Survived
Peridot	Survived	Survived
Black Star Sapphire	Survived	Survived
Tourmaline	Survived = iffy	Damaged = iffy
Denim Lapis	Survived = iffy	Damaged = iffy
Lapis Lazuli	Damaged	Damaged
DO NOT TRY THESE STONES
Amethyst
Aquamarine
Black Onyx
Blue Topaz
Blue Misty Chaldecony
Cameo
Carnelian
Citrine
Iolite
Jadeite
Malachite
Mexican Fire Opal
Rhodochrosite
Rose Quartz
Tiger Eye
Turquoise ------------------------------- Any information that PMC experts might like to add would be welcomed.

Evaluating diamonds

      Diamonds are such a mystery to people. They are beautiful, sparkly, extremely expensive, and many people own at least one, yet understanding how the experts assign them value seems to be some sort of inside knowledge that most of us feel excluded from. And, actually, that's somewhat the truth--Certified gemologists, diamond dealers, and jewelry-store owners have their own techniques, their own terminology, their own tests, and we pretty much have to take their word that they know what they're talking about. But then, isn't that true of many professions? That special knowledge is what makes the true insider, and allows one professional to recognize another instantly.

      Well, I'd like to share some insider secrets to help you to understand diamonds. The biggest and best-kept secret is: They may be gorgeous, but they're far from perfect. In fact, if you swept your garage floor and dumped the dustpan contents into a big 55-gallon drum of jello, stirred it up and then chilled it solid, that's pretty much how much of the world's diamond rough would look--filled with bits and pieces of things. Of course, there are those renowned "fabulous finds"--large chunks of clear material, but those are very rare.

     So the bottom line is, the majority of diamonds have "stuff" in them--bits of other material, tiny fractures, discolorations, pieces of diamond crystal grown in a different direction, little chips, etc. etc. This should actually not be surprising, because diamonds are a natural mineral material, and natural material of any type is seldom perfect. That's what makes it natural, after all. Master cutters can cut around the worst stuff, but diamonds are so precious that each and every bit of rough that can be used, is used. The poorest pieces are slated for industrial use, because there, only hardness counts, not clarity or color. But think about it--other than gold and platinum, what materials do you know of where even their dust is valuable?

     OK, this train of thought leads to certain important truths: One is, the larger the diamond, the more difficult it is to find one without any flaws, and the more precious that stone is going to be. Many people dream of getting a flawless diamond, but the reality is, if you could ever afford a truly flawless diamond (flawless inside and out), you could never wear it. It would have to sit forever in the darkness of a bank vault, because one bump of your hand, one tiny nick, and it's no longer flawless. In fact, the few truly flawless large diamonds in existence aren't even set in jewelry. It's too much of a risk. And, to me, the very worst thing about such perfection in diamonds is that it can now be easily duplicated by synthetic diamonds. If they can grow "perfect" diamonds in the lab, I tend to think that detracts from the allure of a flawless genuine diamond.

    The second "secret truth" is that internal flaws (which diamond experts never never call flaws or imperfections; that's too negative, so they call them inclusions), can be, in small amounts, a good thing. You know how on the TV commercials, the snobby diamond expert intones that "no two diamonds are alike," implying that this uniqueness is what adds to their value? Well, you know HOW they can tell that no two diamonds are alike? Yep, by their flaws--sorry, inclusions. If you were to cut the dirty jello in the 55-gallon drum up into ice-cube-sized pieces, every single piece would be unique, too.

    What gemologists do when they inspect a diamond for certification, is take a finished diamond and put it under a microscope. They look at it from the top, the bottom, and the side. On the desk next to the scope they have a drawing of each view of that diamond with all the facets outlined, and they map every single inclusion, every nick, every thing and its exact location in a special code that they mark onto the drawing. They also evaluate its color, and its cut. When they are done, they have noted every single characteristic of that stone in such a way that it's almost like a fingerprint--an absolutely unique picture of that stone. That's important and valuable for two major reasons:

   1. It proves that that diamond is not a synthetic produced in a lab in four days, but a real gemstone produced by mother earth over hundreds of millions of years.

   2. It protects the owner of the diamond. Without a diamond certificate, you have no way of proving that the diamond ring you brought in for resizing still contains those same diamonds when you get the ring back a week later. (That's another reason why, as a buyer, you always want to build a good relationship with a reputable jeweler whom you can trust.)

    So I hope these insights are getting you to think differently about diamonds. More in my next blog. And, just to let you know--I am now selling small, incredibly gorgeous diamonds on my website, Heart of Stone Studio.