I usually don't take photos of the rough gem material. However, because I had a few questions about what it looks like before it is faceted, I did remember one day to get some pictures of parcels I had recently acquired. Now that I have cut some of those pieces, I have a group of "before" and "after" pictures of few garnets.
Obviously in these photos, the scale is not consistent. However, you can see some typical rough garnet and what was done with it. Most of the garnet rough I have encountered is similar to water worn pebbles rather than a nice geometric crystal.
In some cases, a very fine saw may be used to split the material or remove excess material. However, the bulk of the faceting work is done by grinding off the excess to create each facet of the gem. The faceting process involves first removing flaws in the material and shaping the stone with a coarse grit. Then with a finer grit, each of the facets is cut. Often a very fine grit is used to produce a "prepolish" on the facets. Then each facet is polished with an extremely fine grit or an oxide to produce essentially a mirror finish. It is not unusual for two thirds or more of the original rough material to end up as sludge in the bottom of the splash pan of the faceting machine.
Most faceters in the US try to do precision cutting -- angles chosen are to maximize the light return and all facets properly shaped meeting its neighbors exactly according to a predetermined pattern. Another approach to faceting is what is often labeled "native cut". In that case, the material is cut to maximize the weight of the finished stone, often at the expense of the brilliance. The facets on native cut stones also tend not to meet nicely, they are misshaped and do not line up with each other. One other major difference between "native cut" and precision cut, is the polish.
The short version: Like a number of others who enjoy turning rough into sparkling gemstones, I have found a way to give something back to one of the areas where the gem rough originates. All the money from the sale of the Malawi garnets I have cut will go to the K.I.N.D. fund to provide scholarships for Malawian girls' high school education. See http://www.msnbc.com/the-last-word/introducing-the-kind for the background on the fund.
The longer story...
I have had a soft spot for garnets since I started faceting. Perhaps it is because they cooperated in the polishing stage better than many other types of material. Or maybe it is because the material I had was the common red variety of garnet and red goes well with my favorite color, green, to make the traditional Christmas colors. Probably it is because when I was very young my mother told me that garnet was her birthstone -- and she never had a real garnet.
The second factor in picking this project has been that education has been a huge part of my life. My dad found his vocation as an educator. For a number of years my mother worked as a secretary in an elementary school. And when circumstances allowed her to obtain her college degree, she became a special education teacher. A great many of our family friends were folks they knew from the schools where they worked. Furthermore, the importance of education for girls is something with which I had much personal experience. As a female baby boom child, the world I found had many doors closed for girls. It was just assumed that after high school girls would get some clerical job, or perhaps enter nursing or teach elementary school children or work in a retail store. And generally that career was going to be just long enough to land a husband. Even recreation focused on the boys. Our neighborhood had little league baseball games for the boys all summer long. There was no sports in the community for girls. Because my parents cared so much for the value of education and were willing and able to make the sacrifice needed for the tuition, I went to a private school. There I was exposed to much more than what would have been the case for the girls who went to the local schools. That led to the high school experience and eventual college degree -- an opportunity that many of the girls of my generation never had. I cannot imagine how different my life would have been without the education I was lucky to have received.
The third piece in this project was the Lawrence O’Donnell show on MSNBC. Around the holidays he talked about his experiences in Malawi and the K.I.N.D. fund. The lack of opportunity for girls to get even a high school education is something that would likely keep them and their future families in poverty. Those stories and the images of the young girls stuck with me.
Thus when I came upon a rough dealer's page of garnets with many from Malawi, the pieces came together. All money from the sales of gems I facet from Malawi garnet rough will go to the K.I.N.D. scholarships for the Malawi girls.
It was right at the beginning of a mid-November trip to Costco. We went by the tables that were stacked with books - the kind that made nice holiday gifts. Of course, I had to check out what they had. Perhaps there would be one my daughter would like in her library - the kind with lots of pictures she uses for reference in her illustration work. Perhaps there were some of those, but I never saw them. Instead "Gem: The Definitive Visual Guide" by published by DK had my full attention. It was heading into my cart almost before I could flip through the pages. DK books tend to be exceptional visual treats loaded with terrific images. And the price was not going to break the budget. (It is currently listed on Amazon for $25.)
Gem is the typical large coffee table book size. At 440 pages and over 5 1/2 pounds, it is not a lightweight. Typically, gem books tend to go alphabetically or if they are jewelry focused, they tend to follow historical and geographical lines. I have no clue yet how the ordering of Gem was determined. (Perhaps when I stop just looking at the pretty pictures and read some of the text sections, I will eventually figure that part out.) The good thing about that so far seems to be that you can open just about anywhere and not feel like you have missed something. Perfect for the coffee table book which isn't usually given a front to back read.
Once nice characteristic is that it includes images and information of the rough gems along with cut gems and those in jewelry plus a bit of romancing the stone stories related to the gems. My impression of the contents is: imagine you have the best museum of gems, minerals and jewels and then a tour guide who knows it all - the technical data and the historical details and maybe some gossipy trivia to go along with it all. That is what you will find in Gem.
If you like books on gems, minerals and jewelry, or need a gift for someone who does, this is a must.
I spent the past weekend at the San Luis Obispo Gem and Mineral Show demonstrating faceting. The club had acquired a faceting machine this year and it seemed appropriate to put it to use at the show. In preparation I had dopped up a number of decent sized garnets to use for the exercise. In addition, I brought along some finished stones to show off as well as the Vargas and Herbst books on faceting.
As expected, almost no one had any idea how faceted stones were done. There were a few folks who had some experience with cabochons, had a friend who did faceting, or did metalwork, but only one person indicated they had done any faceting themselves. One of the most frequent questions was how the stones were attached to the dops. I use superglue, so it is easy to understand why that kept popping up. Wax or epoxy dopping would have been a lot more obvious.
It was fun explaining faceting and the machine to the show attendees. Some of the kids were great. For a while I had a four year old helper working the water spray bottle for the polishing process. He definitely got into it and stayed focused until his mother finished a purchase across the aisle and came to get him. Perhaps a future faceter?
I have always had a weak spot when it comes to garnets. It probably started when I was very young and my mother told me that her birthstone was garnet. Back then, what came to mind as a garnet was a dark red gem. Years later when I started collecting gemstones and learning more about them, I found out about the wonderfully green variety that was called "tsavorite". Tsavorite garnets put most of the emeralds I had seen to shame. They were such a wonderful sparkling green! So being biased to Christmas colors by virtue of my birth, how could I not fall in love with a gem that was outstanding in those shades? As I furthered my gemstone studies with the GIA Colored Stones course, I learned that garnets came in other shades ranging from a purple red to orange to yellow to green and some were even colorless.
Then I started faceting and discovered that garnets proved to be cooperative in developing a nice polish. Plus many of the reddish types in modest sizes were quite affordable for a beginner faceter's budget. Occasionally a flaw or "feature" of the crystal would become a problem by ending up where it would cause mischief. More often, I could see included crystals and needles when inspecting under magnification while I was polishing the stone, but these inclusions would not be visible to the unaided eye in the finished gem.
There were basically two problems with garnets. The first was that the larger red garnets often were too dark to sparkle. They just sat there looking red. Not awful, but not as exciting as one might hope. The other was a budgetary one. Rough for tsavorite and other types which would sparkle even when large was quite expensive. Thus my accumulation of garnet rough has tended towards smaller sizes in the darker reddish shades and fewer, even smaller pieces of the lighter colors.
A few months ago a parcel of Mahenge garnet rough followed me home. These garnets tend to be nicely shaped, fairly clean pieces that run from a light peach to a nice medium raspberry shade. When cut and polished, these stones are wonderfully bright. Most of the parcel is smaller sizes -- .5 to 1 carat finished. This launched me into an effort to work through a lot of the smaller garnet rough I still had from many years ago as well as working on the Mahenge parcel. Once the small rough is properly dopped the process of cutting it is usually low stress. The smaller the facets, the quicker it is to cut and polish them. (The flip side of that is a slight loss of attention can yield a significant error given the scale of things.) The bottom line is that the majority of the stones I have cut recently have been garnets. And lots more to come.
Years ago I purchased a parcel of green beryl which included a couple of very long and narrow crystals. Short of using the trim saw to turn these into multiple pieces with more typical proportions, there wasn't much else that could be done with these other than cutting them into elongated emerald cut shapes. Of course, that results in a boring stone. The solution to that problem was the addition of concave facets which created much more interesting optics and a gem that has gotten a lot of positive comments. (Figure 1.)
Figure 1. Green Beryl
So why not try the approach on some slightly larger stones? The original green beryl was under 5 mm. wide. I wanted to see the result in a stone that was in the range of 8 to 10 mm. wide. In searching through the rough I had on hand, I found a few pieces that met the desired width, but would end up with the length more like two times the width rather than the four times of the green beryl. At least for the initial experiments, that would have to do.
The idea was to test some variations on a theme. Take a basic long emerald cut and add concave facets to the pavilion only. The crown would be a standard step cut so the only thing being considered was the impact of the concave facets on the pavilion.
Figure 2. Rose Quartz
The first piece was a scrap of rose quartz that many years ago had been trimmed off a much larger chunk. It had been ignored as useless for a long time and I was surprised to find how well it suited the situation. For this one there would be three concave facets on one side of the pavilion -- center and close to each end -- and two on the other side aligned between the facets on the other side. The concave facets were created so that they closely approached the keel without actually touching it. The width of the facets was about the same as the space between them. The goal / expectation were for the actual facets reflected in other side of the pavilion. (Figure 2.)
Figure 3. Amethyst
For the second stone a piece of amethyst was selected. This one was done similarly to the rose quartz, except that in this case there were three concave facets on each side of the pavilion arranged opposite each other. (Figure 3.)
Figure 4. Citrine
Of course, for the third stone in the series, yet another piece of quartz was needed. In this case, it was a citrine. For the final stone, each side of the pavilion had five concave facets that touched each other. (Figure 4.)
I expected that one of the combinations above would clearly be better than the others. But so far, I have not been able to pick a favorite. Meanwhile, I have acquired a few pieces of rough which have a length to width ratio of 3. So some rainy day, I will get around to the next step in this series. Stay tuned.
I wish I had taken a photo of the rough piece of citrine from which this gem was cut. When I purchased the rough, I was looking for material that I could use for concave faceting. It was during of one of my false re-starts for faceting and I don't remember if I thought I would saw the rough into multiple pieces or use it for a single stone. When the time finally came last fall that I took it out of the drawer for faceting, I ended up preforming it to be a single rectangular cushion stone. Other than knowing that I would use the OMF machine to put concave facets on the pavilion, I had no idea how I would cut it. It got dopped along with ten or so other stones. They got cut. This one sat there being big and intimidating. Another ten or so stones were dopped and cut and the big citrine still had not touched the faceting laps. It was now the new year and I decided that I could no longer allow that stone to intimidate me.
The first step was to find the outline and the pavilion keel. I started roughing in the shape with the lap I typically use for such purposes and after a bit realized it needed a coarser lap. Once I got the outline figured out it was time to think about the details with respect to facet placement including the concave ones. The initial pavilion facet pattern was a basic step cut. Typically, that makes for a pretty boring gem. However, concave facets placed in the pavilion usually light up the stone and make it more visually interesting.
I decided on three concaves on each side of the pavilion with a bit of space between them. They were placed such that they centered on the middle step extending towards the keel and the girdle, but not touching either. Often the keel on quartz is easy to chip, so keeping the curves away from that area means that should chips appear in the future as a result of handling, the repair required would be minimal.
Then it was time for the crown. Again, the first step was to level the girdle and rough in the shape. After a good night's sleep, I decided that the crown would consist of flat facets only. Rather than using a routine step crown with a large table, additional rows of facets were used so that they and the table were about the same width. When the stone was removed from the dop, the results were as desired. The long facets on the crown made it seem like there were multiple sets of concave facets on the pavilion.