| Checkmate - Reflector (SIG8.JRG) by Jeff R. Graham jeff@faceters.com ©2000 | |
|---|---|
| Angles for R.I. = 1.54 | 53 facets + 16 facets on girdle = 69 |
| 4-fold, mirror-image symmetry | 96 index |
|
L/W = 1.000 T/W = 0.199 T/L = 0.199 P/W = 0.435 |
H/W = (P+C)/W+0.02 = 0.672 |
| Vol./W^3 = 0.244 | Brightness at 0 degrees tilt for R.I. = 1.54 COS = 86.5% ISO = 92.9% |
| GemRay Ray Traces | ||
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| Random Model | Cosine Model | ISO Model |
| Pavilion | |||
|---|---|---|---|
| P1 | 41.00 | 96-24-48-72 | Cut to center point. |
| P2(G) | 90.00 |
96-06-12-18-24-30-36-42 |
Cut a level girdle. |
| P3 | 58.00 | 06-18-30-42-54-66-78-90 | Cut to meet P1, girdle. |
| P4 | 66.23 | 12-36-60-84 | Cut to meet girdle, P1. |
| Crown | |||
|---|---|---|---|
| C1 | 42.40 | 96-24-48-72 | Cut to meet girdle |
| C2 | 44.50 | 06-18-30-42-54-66-78-90 | Cut to meet girdle |
| C3 | 38.57 | 12-36-60-84 | Cut to meet girdle |
| C4 | 34.13 | 09-15-33-39-57-63-81-87 | Cut to meet girdle |
| C5 | 29.40 | 96-24-48-72 | Cut to meet C1,C4. |
| C6 | 28.00 | 12-36-60-84 | Cut to meet C3,C4,C5. |
| C7 | 20.50 | 96-24-48-72 | Cut to meet C4,C5,C6. |
| T | 0.00 |
Table |
Cut to meet C6,C7. |
Shown at right and below is a 13mm ~7.72 carat "CheckMate" cut from flawless Maraba Amethyst by Jeff Graham. "CheckMate" performs well with low RI materials like quartz and beryl.
This is a neat one, the flashes are a true check, or square, something a brilliant bottom will not do. This is not any harder to cut than a standard checker. As the stone gets large, the flats on the bottom take some time and caution when polishing. It should be cut in a larger size, and medium to light color.

Left: This Maraba Amethyst "CheckMate" is not as pink as this picture might make you think it is, although it does have quite a bit of magenta shot through it. What you are seeing in this picture is the reflected colors from the surroundings when the photograph was taken (we were in just a normal room with white walls). This design seems to reflect and mirror everything around it, which makes it hard to take a picture of, but a very pretty design.
I think that this works well in almost any medium to light colored stone, you can really see the check squares as the material gets towards the light side. It is best in a larger stone, I would say at least 8mm, I prefer it in 14mm. It makes great earrings and reminds me of the old hand cut buttons that used to be put on coats. Have fun and let me know what you think... If you have questions or need help with your CheckMate, feel free to email me jeff@faceters.com.