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Yeah, I know it’s been far too long since I posted anything with substance. I’ll do my best to get something out this week. For now, here’s something I was playing with — with positive results for a change!
3.13ct CZ in my Retro-hex design. It’s hardly a novel design in the cutting world, but I can lay some claim here as I did this one from scratch. I’m waiting for my machine to come back from the shop so I can try some other ideas I’ve had a few weeks to ponder.
For the record, the image above is hosted by Flickr. Flickr makes things rather easy and gives double-exposure (which may come in handy if I ever go back in to business). Feel free to click the image and poke around my other pics.
| #13, Dark Green CZX | ||
|---|---|---|
| design | Light House (Jeff Graham) | |
| weight | 2.43ct | |
| dim. | 6.9×6.9×4.0mm | |
| date | 1/10/2007 | |
CZX is the trade name for blue and green cubic zirconia. This particular color looked promising when I bought the lot, but an earlier stone proved that it cuts out pretty dark. Since near-black stones, don’t have much appeal for me I have been looking for ways to lighten up the look of this material. Stone #13 represents an experiment based on some advise I was given by a professional faceter.
The sum of the advise was to minimize how much internal reflection the stone had. So I chose a simple design and made the pavilion angles as close to the critical angle of CZ as reasonable. Jeff Graham’s Light House has a very simple pavilion (check out the design schema), so it was a great starting point. All I had to do from there was reduce the pavilion angles. The stone turned out fairly thin, but not dangerously so; it’s still setable.
The technique did work somewhat — this stone has more green to it than my first attempt with this dark green CZ. It also has a very slight bit of dispersion when you rock the stone back and forth. It is still not what I had in mind. Guess I’ll have to keep experiementing with this stuff — it’s good practice cutting anyway.
| #14, Amethyst | ||
|---|---|---|
| design | Gram Easy Emerald (Jeff Graham) | |
| weight | 2.33ct | |
| dim. | 9.92×5.70×5.66mm | |
| date | 1/11/2007 | |
This stone was also something of an experiment for me. It is my first emerald cut (that was experiment enough) and it was my first use of a preform. By “preform” I mean piece of rough that popped off of someone else’s dop — they were so aggravated, they handed the rough to me “for practice”.
The picture you see here is somewhat ironic because you’ll note the window in the top-middle of the stone. That window is caused by the camera angle — you won’t see it head on…. but what you will see is a dark center where the light cancels itself out. The crown is too high; if this stone were round, I’d call it a nail-head. You can see the cancellation effect in the far left bezel facets.
Despite the dark center, I’m pretty happy with this one. The color is even and has a velvety quality (it looks far too washed out in the picture here). Maybe I’ll recut this stone someday.
It has become something of a tradition for us to go rock hunting on Thanksgiving day. This year we managed to sneak out a few days before Thanksgiving because that’s when Grandma volunteered to watch the kids.
Since we were in Delaware, we decided to take a little car ride and visit Cape May, NJ. Cape May is the southern-most part of New Jersey. It’s a pretty town and we enjoyed wandering the near-vacant streets of the tourist district. We especially enjoyed eating at the locally-famous Lobster House near the edge of town. It’s a pricey restaurant, but there is a diner portion that the locals frequent (same food, somewhat smaller portions and much smaller prices). I’m not sure I would like to be in the town or the restaurant during the “on” season when the town is packed with tourists.
A little online research told me that the place to find Cape May diamonds is on Sunset Beach. The signs for it are not very good, so a local map was helpful. Fortunately, these are freely available at the Ferry station.
Sunset Beach has two claims to fame. The abundant Cape May quartz and the wreckage of a WWI concrete boat just off shore. The wreck of the Atlantis and it’s place in naval history is pretty well documented online, so I’ll leave you to Google that for yourself. One website I read suggested that the wreckage was responsible for redirecting the “diamonds” to shore on Sunset beach.
The day we visited the beach, it was cold and blustery. We were eager to hunt “diamonds”, so we braved the wind hit the beach. Fortunately, we didn’t wait — when we left Cape May the next day, it was about 35 degrees and driving rain!
The beach is a combination of sand and pebble. The great majority of the quartz is pretty typical for the northeast, mostly opaque to translucent white pebbles. Mixed in are orange and occasionally purple pebbles of quartz, but these are always opaque. The colorless “diamonds” are hard to miss once you see them, they have a high translucency when they’re wet. The crystal quartz gives them a distinct sheen or glow, even in the gray diffused light we had that day. The “diamonds” are abundant enough that we took to high-grading pretty quickly after we started finding them.
Sunset Beach would be a great place for kids who are into rocks. The “diamonds” are just hard enough to find that you have to look for them, but abundant enough that everyone will find some. We came home with a healthy zip-lock bag full — though some were not “diamonds,” but pretty rocks to add to our kids’ collection. When our little guys are old enough, we’ll certainly head back to Cape May and let them collect some.
The largest “diamond” we found was an elongated tear-drop shape measuring 28×15x9mm (not pictured). It would have been a wonderful piece to facet except for the large white feathers and healed fractures. Unfortunately, the great majority of the colorless quartz pebbles you’ll find have such inclusions; pretty much what you’d associate with low grade colorless quartz from the Northeast.
The best stones we found are the four pictures here. As you can see, none of them are large. All of these are internally perfect and will likely cut flawless stones. The best of the lot is the triangular shaped one, measuring 9×9x5mm. I doubt anyone but a hobbist would cut quartz this size (though someone is cutting it: the souvenir shops advertise “Cape May Diamond jewelry”). I’ll likely cut one just for the sake of having a cut piece to put in my display with the rough.
I could not find information online regarding how large Cape May “diamonds” form. But after having hunted the beach, I would be very surprised if the facet-grade ones come any larger than the ones we found. Still, the souvenir shops were mostly closed during our visit, so I didn’t get to view any of the commercial jewelry they offer to know how large their finished stones were. (We did visit some of the estate jewelry shops in town, none of which had Cape May “diamond” jewelry.)
If you’re looking for facet rough that you can find on your own in the Northeast, I’d head to Herkimer. If you’re looking for a fun day on the beach with some easy rockhounding, Cape May is perfect.
| #10, Synthetic Color-Change Sapphire | ||
|---|---|---|
| design | A Round Cushion (USFG) | |
| weight | 8.52ct | |
| dim. | 12.06×12.05×8.02mm | |
| date | 11/1/2006 | |
Last night I finished stone #10, a color change synthetic sapphire cut into a cushion shape. I’m quite pleased with how the stone looks — which is great because I intended it for a show & tell stone while we visit family this month. But that is not to say I’m satisfied with it. I can’t bear to put the thing under a loupe right now — there are just too many mistakes for the amount of time I put into it. I keep reminding myself this is stone #10, not #100.
Here are three shots of the stone. The largest picture of the stone is probably how you would see it in person. The picture was taken under mixed lighting in our kitchen. The dark reddish purple color is how the stone looks under incandescent lighting, while the medium blue (my favorite) is under fluorescent lighting. The stone is clean, but I wasn’t very careful with my photography so you can see some fingerprints and dust on it. The wavy look in some of the facets at the top of the stone is a reflection from the cork it’s sitting on. (There are some tiny polish lines, but you need 10x magnification to see them.)
I joking call this material “Grandma’s Alexandrite.” It seems that whenever I’m handed a largish gemstone with the a story starting “This Alexandrite came from my Grandmother…”, the gem material is synthetic color-change sapphire. Synthetic sapphire has been around since late 1800’s, color change material from the early 1900’s. Natural Alexandrites are rare; large ones are extremely rare; large Alexandrites that are completely free from inclusions are practically unknown. The upshot is some poor gemologist or jeweler is left trying to explain to someone as gently as possible that their Grandmother’s stone is man-made and quite common. Fortunately, synthetic sapphire is beautiful in it’s own right.
Every now and then the kids ask to look at pictures on the computer. In going through them this morning, I realized I forgot about this one. I really should have posted it sooner. Grandma was picking through a parcel of mixed gem rough I recieved from a friend. The kids wanted to join in, so they started sorting things by color. They sat there for a good 45 minutes playing with the “pretty rocks.” I’m glad I was smart enough to take a couple pictures.
From now on I get to sign my name as “Peter Torraca, GG”. I received a letter from the GIA that I passed my final exam in their Graduate Gemologist course. It is a huge relief to be officially finished!
Though, to be honest, my enthusiasm is a little subdued. I am keenly aware of the fact that I could have, and should have, finished the degree much sooner. I started it while Karen was in grad school at the Univ. of Florida. Life, and more than a bit of my innate laziness, got in the way. Thinking back, I realize it took me 7 years, 3 states, and 4 mailing addresses to get it done(!). I would have been a better candidate for the GIA’s residence course. It wasn’t until the Lord taught me a little something about stewardship of opportunities (especially ones I’ve already paid in full for) that I got back in gear and pushed for the finish.
It is strange, I feel more confident and capable in the world of gemology today than I did yesterday, though nothing has changed in my knowledge or skills. It is amazing what external affirmation will do for one’s outlook.
Is there something you’ve been “working on” over the years that really should be completed? Don’t wait any longer, it feels great to get it done and not have it always hovering the background!
| #4, Hudson River Glass | ||
|---|---|---|
| design | Easy Cushion (Jeff Graham) | |
| weight | 1.81ct | |
| dim. | 8.00×8.00×5.73mm | |
| date | 6/18/2006 | |
“Hudson River Glass” is the name I’ve given to facetable bottle glass you can find along the banks of the Hudson River in New York. This stone came from a very worn piece of antique blue glass — likely an apothocary or cosmetic jar. Bottle glass is fun to facet because it takes a polish nicely and really isn’t difficult to work with. The down-side is that the material is soft, so it has to be handled gently. I learned this fact the hard way — this stone has a chip on it’s girdle from my fumbling in trying to remove it from the dop.
Some people dream of being surrounded by gemstones. This little guy looks rather unhappy to be included in the dream.
Both pictures are of a fingerprint in natural Ceylon (?) sapphire. The “face” is a network of small tubes, likely a healed fracture in the crystal. The “eyes” are tiny included crystals.
Both pics are approximately 30x. The first pic (orange background) was taken through under cross-polarized filters. Pic second was taken with darkfield lighting. Both pics demonstrate my hack-level skills at photomicroscopy, but were fun to take. So passes today’s nap time.
Working through my GIA gem sets, I found that this syn. star sapphire cabochon made it’s own condensing sphere when placed in the polariscope. It displayed a rather obvious uniaxial optic figure. A uniaxial figure is typical of this material, but usually not this easy to see. I couldn’t help taking a pic.
A friend of mine pointed out a very interesting article at Yahoo News (citing a LiveScience.com article). It seems that researchers at the Carnegie Institution’s Geophysical Laboratory have figured out how to make a CVD diamond around 10ct total weight. That’s a big deal as synthetic diamonds have been pretty much limited to the 3ct range. The title’s “300ct diamond” is theoretical, but I suspect it’s not far off in the future. Here’s a link to the original article on Yahoo News (no clue how long it will be available):
http://news.yahoo.com/s/space/20050517/sc_space/newtechniquecouldmake300caratdiamonds
My friend made an insightful comment: “Wonder what that would do to the industry. What kind of affect did cultured pearls have on that market? I guess those can be distinguished from real ones though.”
His comparison to cultured pearls is apt. When those hit the market in the early 20th century, there was mass-panic in the industry. Thanks to some very innovative gemologists, tests were designed to distinguish cultured pearls from natural pearls. (And the forerunner of GIA’s Gem Laboratories were created in the process.)
Sure, cultured pearls gave confidence-men an opportunity; shysters still try to pass cultured pearls off as natural pearls. But overall, the benefits outstrip the perils, especially for those behind the jewelry counter.
Natural pearls are astoundingly rare. Most people never see a gem-grade natural pearl in their lifetime, much less own one. Retailers discovered that instead of killing the market, cultured pearls opened a new niche. Pearls were once reserved for royalty; here in Indiana, one Indianapolis jeweler advertises pearls as a great gift for girls graduating high-school.
I think synthetic diamonds will follow a similar path and it will happen quickly. Because gemology is much better established than it was when cultured pearls were introduced, the labs are already able to distinguish synthetic from natural diamond. The science is so far advanced that publications like Gems & Gemology have released a host of articles and charts helping your friendly neighborhood gemologist distinguish man-made from naturally occurring. Most recently, G&G has released a compendium of the research published on detecting synthetic diamonds called
“Gems & Gemology In Review: Synthetic Diamonds”. Equipped with this kind of information, it’s reasonable to expect a knowledgable gemologist to separate most natural diamonds from synthetic diamonds. Ironically, in some cases, the separation is easier than separating pearls(!). Of course, since the definitive tests require a well equipped gem lab, certification of significant stones is highly recommended.
As news of gem-quality synthetic diamonds makes its rounds through the media, some people will panic (especially dealers who peddle diamonds but don’t really know diamonds gemologically), but things will settle down. In the end, it will be very much like pearls: 1) if you don’t know, assume it is synthetic and 2) get lab certification on everything that matters.
The fashionable elite will always dish out the cash for certified naturals. Everyone else (read here: you & me) will be happy with the small naturals or the big synthetics. In the end, provided you know what you’re buying, sparkle is sparkle.
