Talk:Akhavan - Cyclops

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This design was written for a 60 gram piece of clear quartz I picked up in Peru. The issue was that the best yield for this piece was to have a rectangular cushion in the L/W = 1.3 range, but the closest I could get in a working design was L/W = 1.25-ish. During the design phase, the face-up reflection at one point was highly reminiscent of a cyclops, but I fooled around with the design and got MUCH better light return by adding the pavilion splitters. It's much brighter in person, and has nice tilt performance. (I figure I should mention that all the renders I have up use a head shadow.)

The design works in RIs from quartz to moissanite with no changes. I definitely do NOT recommend any materials with a lower RI (so no feldspars or fluorites). If you're cutting this in something with high dispersion, consider raising the crown a bit - BUT, as-is, cutting this in GGG/CZ/ST will give you ridiculous dispersion. Be warned! When I cut this with GemRay in CZ, I optimized it and broke the rendering process. Take a look at the bottom of this discussion page.

Unfortunately, I didn't realize how difficult I was making this design. There are four 7-facet meetpoints, and twelve 5-facet meetpoints. Even worse, many of these complex meetpoints are codependent - some single facets will meet two or more of these meetpoints at the same time, so if either meet is off, it'll really show. Case in point - the C10 facet will meet the cluster and the meetpoint (C4, C6, C8, C10, C12) at the same time. Thankfully, there aren't ay particularly shallow crown facets, and there aren't any facets that are really close in index and angle.

While I'm talking about the C10 facet, please note that it DOES NOT MEET at the meetpoint (C5, C8)! It comes very close, but doesn't actually touch it.

And honestly, I have no idea what the hell to do with a stone this big. Thoughts?


Difficulty level = high intermediate


Post-test cut additions:

In quartz, this design has a much larger than expected tilt window. The renderings are NOT accurate - expect more windowing when the stone is tilted.

Cyclops (render, CZ).jpg