I Facet A Large Rose Quartz Into A Pixel Cut

Hello everyone, I'm Matt, this is Matt's Corner of Gem Cutting, and in this video I'll be cutting this chunk of rose quartz. The starting shape of the piece isn't ideal. It has an odd shape with some large divots and thinner areas getting quite shallow for cutting compared to its width, which will affect how large of a piece I can cut from it. Still, it is as nice of a piece that I was able to find in rose quartz for its size. There are a couple fractures headed into the interior of the stone. Since the rough is a little on the thinner end and having those fractures, I think that it will be best to actually cut the stone along the fractures and do two pieces from the rough. The starting weight of the rough is 355 grams, or just over 3 quarters of a pound. Multiplying the gram weight by 5 gives us the starting carat weight, which is 1,755 carats. I draw a line along the fracture path around the stone so that I can easily see how to align the stone for sawing it along those fractures. Now that it is in two pieces, the smaller piece weighs 146.51 grams, or about 732 carats. The larger one weighs 204.78 grams, or close to 1,024 carats. Looking over the larger piece, I think that the orientation will be best, with the largest face of the piece being the top of the gem. With that side oriented up, the bottom of the stone already starts forming a point, which is decent for starting shape. There is a big divot on the top I'll have to grind out, which will affect the depth I have to work with. The smaller piece looks like it will be best oriented with the sawed edge being the crown side of the stone. The opposite side of that is a little more rounded or pointed, which will be better suited for the pavilion. So that is the way that I'll orient it for faceting. I'll go ahead and get both of the pieces lightly preformed. So rose quartz is the pink variety of quartz and is often cloudy or milky. The little inclusions that cloud up the material are also what give rose quartz its light pink color. Most rose quartz material doesn't have good enough clarity to be good for faceting, especially larger pieces. I went through tons of material a vendor had at one of the Tucson gem shows, but most of it was highly clouded or had lots of fractures. I felt pretty lucky to find a larger piece this nice. Localities that are known for having better quality rose quartz are Brazil and Madagascar. This piece came out of Madagascar. Here the pieces are preformed. I mostly flattened the area that I will be dopping to and ground down the rougher edges. I didn't do a whole lot of shaping other than it did take a bit of grinding to mostly get out the large divot in the larger piece. The larger piece is down to 894 carats. The smaller is at 700 carats. I often will pick out or create a design for a stone between preforming and before dopping, but I am certain that it will take me a while to come up with the designs, so I am just going ahead with dopping. I center the dop according to the general length and width measurements. I attach the dop with glue and coat with baking soda for some added strength and quicken set time. Using the length, width, and depth measurements of the rough, I will be able to find or create facet diagrams that will work for the pieces. Now before I get to that, Flexispot is back sponsoring this video with their C7 Max ergonomic office chair. Once again, I have the mesh version, which I prefer, though they do offer a foam cushion. The mesh is good material, it is comfortable, and feels nicer than that on another mesh chair I have. Like the C7, the Max has the adaptive lower lumbar support, which moves with you, supporting both the lumbar and sacrum. Other features it has like the C7 include the adjustable seat depth and being able to lock the backrest position. Next to the height adjustment, there is a knob that can be rotated to change the counterclockwise for easier tilting and clockwise to be more stiff. The C7 Max has upgraded 5D armrests with the soft foam cushion. The upper arm can be rotated 360 degrees and the lower arm 240, allowing for a wide range of where the armrests can be adjusted to. The height of the entire back of the chair can be adjusted on the C7 Max, so whether you are taller or shorter, you can adjust the back support to where it feels best. The 3D headrest of the C7 Max has two pivot points, giving it increased adjustability. This chair has the optional footrest, which is really easy to flip out. It tucks away neatly under the chair. I like the added adjustability and features of the C7 Max, and I do think that the Max is overall more comfortable than the C7, which was already quite the improvement over my chair before it. You can use my code C750 to get $50 off the C7 Max. You can also consider other options like the budget-friendly C5 chair and their newly launched C7 Morpher chair on their website to find the chair best suited for your needs. You can check the video description for links and more information. Alrighty, I am ready to get grinding on this piece. I have been wanting to do a large pixelated cut, so I designed one for the larger piece. I haven't done the design for the second piece yet. I will only be fastening the larger one in this video and save the second for some other time. So if you have any suggestions for what you might like to see the other piece become, let me know in the comments. So a pixel or pixelated cut is a cut that creates the optics of a bunch of small pixel-looking boxes in the gemstone. This is achieved by fastening a bunch of step cuts on the pavilion and crown of the gem that run perpendicular to each other. So the pavilion steps all cut one way and the crown steps go the other. I call this cut 360p because it consists of 18 of those step facets on the pavilion that cross with 20 step facets on the crown. 18 columns crossed by 20 rows would make 360 pixels. Technically, the design doesn't quite make 360 as some of the facets don't cross each other on the edges of the stone where the corner and side facets are, but based on the math, that is what I called it. Originally, I wanted to make a pixel design that totaled up to 1080 pixels. This would be 30 step facets on the pavilion and 36 on the crown. I gave up on trying that as the angle change between the steps would be too low to be practical for faceting for the design to look good. Having a very small angle change between facets cut in line with each other can become problematic. It can cause facets to not have a crisp facet line between them, possibly even blending together. And any error to rotation and tilt of the facet is magnified, making it more difficult to produce a nice even looking facet. Facets very close in angle to the one in line before it also cut very quickly, making it easy to overcut facets. For a 1080 design to look good, the angle change would need to be closer to 0.75 degrees between the pavilion facets, which is too low of a change in my opinion, especially if not using super precise equipment. The 1.5 degree angle change of the pavilion steps is already troublesome enough on this stone. I like the idea of the 1080 design, but I don't think I will ever do it. I thought of it because it would sound like the 1080 full HD resolution, though my design would have had a total of about 1080 pixels where the full HD resolution has 1920 by 1080 pixels, so my design would still only count for about one row of the pixels at that resolution. Going off the naming standards for resolution sizes, maybe my 360p design would be considered 18 or 20p resolution. So far, I have gone through using a series of topper laps to grind in the facets, starting with a 60 grit for rough shape and going over each pavilion facet at the 180, 300, and 600 levels. I'll now use 3000 grit diamond paste on a tin lap to prep the facets for polish. Over time, swarf or just a bit of gunk builds up on the lap which I need to wipe off. I also lubricate the lap with more oil whenever it starts drying out and apply more diamond compound whenever the cutting becomes slow. The polish is done using cerium oxide on a dark side lap. This is done at low speed with just a light amount of moisture on the lap. Polishing can be a lengthy process. Most of the facets on this stone took at least 5 minutes or more to polish. The pavilion is finished, so I will now transfer the stone to a V-Dop so that I can switch to cutting the crown facets. After the glue has set, I use heat to remove the flat dop. Okay, so I had a little bit of a mishap. Somehow, I managed to crack the stone. It definitely happened at some point while I was heating off the flat dop. The stone did get quite hot. I didn't have the paper towel as wet as I usually have it. And it took quite a while for the dop to come off, letting it build up a lot of heat. I'm not sure if it was the heat alone, or also getting a little rough with the pliers testing the dop to see if it would come off a few times. But at some point, it got a crack. It runs a little less than halfway across the stone. I don't think that it overly affects the integrity of the piece to where it will easily break, so I will still finish it. But that crack will be a bit of an eyesore in the finished piece. Besides the regular foggy inclusions in rose quartz, this piece was free of fractures or any bad inclusions, so it made my heart drop seeing the crack after removing the paper towel. It is what it is, though. I should have been more careful, but that is part of the piece now. I can't change what happened, so I will work with what I got. Luckily, this is one of my own stones. It would have been extra sad if I cracked some client's special stone or something like that. The process of cutting the crown facets is the same as I did for the pavilion. I run back through all of the topper laps. One thing about using the cheap topper laps is that they can stick up slightly more towards the outer edge. This will cause facets to cut unevenly depending on the position that they are held to the lap. Because of this, I try to not swing the stone very far towards the edges when cutting in the facets. But this stone has long facets with small angle changes, so I still had some unevenness showing up in the facets. The only other issue is that the facet edges with very large angle changes kept developing little chips throughout each stage, including polish. Sharp edges tend to chip easily. The areas that were chipping on this stone were along the girdle edge and along the edge of the large side facet where it meets the shallow step facets. So how much force do I use when holding the gem to the lap? I use just enough to hold the stone firmly to the lap. Exerting too much force can cause the stone to catch or dig into the lap, often causing damage to the stone and lap. A lot of force can also cause the stone and dop to rotate slightly in the facet head, causing alignment issues. And exerting more force doesn't really help the stone cut faster. A lot of force will even slow or stop the lap from rotating altogether. I do want to fill some drag though, which indicates that the stone is grinding as it should be. A sense for how grinding a gem should feel when pressed against the lap is developed over time through faceting experience. Things like lap speed, amount of lubricant, and pressure used all contribute to what the drag of the stone on the lap feels like. And each aspect will be changed up some depending on the laps being used or which stage of the faceting the gem is at. This design doesn't have a table facet, so once all of the step facets on the crown are done being polished, the stone is finished. One thing I was worried about is how well the pixels would show up since rose quartz is a little cloudy, but it looks like they are showing up just fine. Anyway, I'll give the stone a nice long soak in acetone to dissolve the glue. Trying to heat off the dop touching finished facets would definitely cause some surface damage to the stone. I definitely don't want any more damage, so I'll be patient. Okay, I think that the stone turned out pretty decent. By all means, the faceting isn't perfect. The step facets aren't perfectly matched for size, and there is some alignment issues that can be seen. There is also some light chipping, but it still achieved the pixelated look that I was going for just fine, and it looks pretty good. The stone finished at approximately 48.25 by 35.25 millimeters and weighs in at 318.5 carats. Definitely a large piece for this clean of rose quartz. If it weren't for the fracture, this piece would easily value over $20 per carat, but since I messed it up, I think that its value is closer to $12 per carat, putting the value of this stone at $3,800. The other chunk of rose quartz won't finish as big, but maybe I can manage to not crack it. If you do have any thoughts on what you might like to see that piece become, let me know in the comments. Thank you.