So, I recently purchased a diamond ring for my girlfriend, which I'm very happy with, but I am curious about the stone and have been lurking and reading here. It's a .68 D SI2, with a table of 61, a crown angle of 32 and a pav angle of 41.4.
I guess you would call that shallow / deep? I think it looks excellent (stone was chosen by working with a third-generation local jeweler in the town my girlfriend is from, might have gone a different route if I had found PS first but I am happy with the stone and with supporting local business), and I knew when I got it that it was going to be a little low-fire, but the brightness is tremendous.
However, I've noticed that it is hard to find stones so close to .70, presumably because of the price jump at .7 (this is one reason I went with the stone despite it being a D - a slightly bigger stone would have been a lot more expensive, and while the stone is ordinary as diamonds go with regard to size and cut, not that many people own Ds). From my amateur understanding of cutting, the deep pav is to try to save weight, and the flat crown is to make up for the deep pav (%ages are 12.5 and 44.0) without ruining the stone. But despite the cutters best efforts, they seem to have come in below .70.
So, I have two questions about cutting. First, can we extrapolate anything about the rough diamond, in terms of the size / location / type of whatever hypothetical defect would have caused it to be cut in this way? Second, am I right that the flat crown and big table are a response to the deep pav, or is it more likely that the defect in the rough stone caused the flat crown directly, i.e. would the cutter have preferred to reach .70 even if it meant making a steep/deep stone?
In general, is there much information out there about shallow / deep stones like mine? All I've found are comments that flat crowns compensate for deep pavs, and that at pav angles above 41.0 HCA is unreliable.
FYI, stone gets a 3.5 from HCA and a 2A on the AGA tool. The GIA report it came with indicates VG. I guess I should post full stats (that I have):
GIA
.68
D
SI2
Very good cut
5.70 mm x 5.75 mm x 3.43 mm
Polish VG
Symmetry VG
Fluorescence: Faint
Table: 61%
Depth: 59.9%
Crown angle: 32.0
Crown depth: 12.5
Pav angle: 41.4
Pav depth: 44.0
Star facets: 55%
Lower pav: 80%
Girdle: Med
Cutlet: None
Yesterday I finally managed to get decent indoor photos, so I have pictures too. First is head on in bright light but with my head blocking the sun, second is with me ducking so its direct light, third is just for fun, with the sun behind the stone. This morning I took the ring outside, and the last shot is my best effort from that.
Also, I am putting this in Rocky Talky because I am curious about cutting, but if it should be moved to Show Me the Bling please do move it. Thanks!
I guess you would call that shallow / deep? I think it looks excellent (stone was chosen by working with a third-generation local jeweler in the town my girlfriend is from, might have gone a different route if I had found PS first but I am happy with the stone and with supporting local business), and I knew when I got it that it was going to be a little low-fire, but the brightness is tremendous.
However, I've noticed that it is hard to find stones so close to .70, presumably because of the price jump at .7 (this is one reason I went with the stone despite it being a D - a slightly bigger stone would have been a lot more expensive, and while the stone is ordinary as diamonds go with regard to size and cut, not that many people own Ds). From my amateur understanding of cutting, the deep pav is to try to save weight, and the flat crown is to make up for the deep pav (%ages are 12.5 and 44.0) without ruining the stone. But despite the cutters best efforts, they seem to have come in below .70.
So, I have two questions about cutting. First, can we extrapolate anything about the rough diamond, in terms of the size / location / type of whatever hypothetical defect would have caused it to be cut in this way? Second, am I right that the flat crown and big table are a response to the deep pav, or is it more likely that the defect in the rough stone caused the flat crown directly, i.e. would the cutter have preferred to reach .70 even if it meant making a steep/deep stone?
In general, is there much information out there about shallow / deep stones like mine? All I've found are comments that flat crowns compensate for deep pavs, and that at pav angles above 41.0 HCA is unreliable.
FYI, stone gets a 3.5 from HCA and a 2A on the AGA tool. The GIA report it came with indicates VG. I guess I should post full stats (that I have):
GIA
.68
D
SI2
Very good cut
5.70 mm x 5.75 mm x 3.43 mm
Polish VG
Symmetry VG
Fluorescence: Faint
Table: 61%
Depth: 59.9%
Crown angle: 32.0
Crown depth: 12.5
Pav angle: 41.4
Pav depth: 44.0
Star facets: 55%
Lower pav: 80%
Girdle: Med
Cutlet: None
Yesterday I finally managed to get decent indoor photos, so I have pictures too. First is head on in bright light but with my head blocking the sun, second is with me ducking so its direct light, third is just for fun, with the sun behind the stone. This morning I took the ring outside, and the last shot is my best effort from that.
Also, I am putting this in Rocky Talky because I am curious about cutting, but if it should be moved to Show Me the Bling please do move it. Thanks!
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